Xavfsizlik tadqiqotchisining bu hafta e'lon qilingan topilmalariga ko'ra, Tailscale tarmog'idagi bitta buzilgan qurilma orqali u erisha oladigan boshqa serverlarda root huquqiga erishish mumkin.
Hujum ikki narsani talab qiladi: port yo'naltirishni ruxsat etadigan tarzda sozlangan Tailscale SSH va tarmoqning kirish qoidalari maqsadga ulanishga ruxsat beradigan, allaqachon bir qurilmani nazorat qiladigan hujumchi.
Topilmalar 25-oktabrda Cyberdione Labs'dan Erika Windisch tomonidan Tailworm deb nomlangan hisobotda e'lon qilindi. Windisch Tailscale 1.104.2 versiyasini va ba'zi tarmoqlar kompaniyaning xostlangan xizmatidan foydalanish o'rniga Tailscale'ni o'zlari boshqarish uchun ishlatadigan headscale 0.29.5 versiyasini uch kun davomida laboratoriyada sinovdan o'tkazdi.
Hisobot haqiqiy tarmoqlarga qarshi hujumlarni emas, balki shu dasturiy ta'minot ustidagi sinovlarni tasvirlaydi. Nashr etilgan paytda Tailscale hech qanday xavfsizlik byulleteni, CVE identifikatori yoki tuzatilgan versiya e'lon qilmagan.
Tailscale ommaviy javob berdi. Kompaniyaning muhandislik bo'yicha vitse-prezidenti Mayk Shaver Reddit'da Tailscale hisobotni olganini, o'sha sohalarni tashqi xavfsizlik mutaxassislari bilan allaqachon tekshirayotganini va tuzatish ustida ishlayotgan muammolarni topganini yozdi. Shaver kompaniya hali qaysi sozlamalar ta'sirlanganini aniqlash ustida ishlayotganini va "barchaga Tailscale SSH'ni o'chirishni tavsiya qilmayotganini" aytdi.
Tailscale SSH oddiy SSH serveri kabi ishlamaydi. Ulanayotgan foydalanuvchining paroli yoki kalitini tekshirish o'rniga, u qurilmani aniqlaydi va yagona kirish qoidasi shu qurilma maqsadga SSH sessiyasini ochishi mumkinligini hal qiladi.
Shu sababli hujum o'g'irlangan parollar yoki kalitlarni talab qilmaydi. U avval bitta qurilmada o'rin olishni talab qiladi, hisobotga ko'ra hujumchi buni odatiy usullar bilan olishi mumkin: zaif veb-ilova, zaharlangan dasturiy paket, fishing yoki o'g'irlangan kirish ma'lumotlari. Tailscale bu birinchi o'rinni yaratmaydi.
Administrator qanchalik chora ko'rishi mumkinligi tarmoq qayerda ishlatilishiga bog'liq. Tailscale'ning xostlangan xizmatida yo'naltirishni har bir qoida bo'yicha o'chirish mumkin. Headscale 0.29.5 versiyasida esa yo'naltirishni umuman o'chirib bo'lmaydi. Hisobotga ko'ra, u yerdagi har bir SSH ruxsati maqsadda root berish deb qaralishi kerak.
Laboratoriyada Windisch muammoni bosqichma-bosqich ko'rsatdi. Standart SSH port yo'naltirish yordamida oddiy sessiya root darajasidagi Tailscale jarayonini faqat root kirishi kerak bo'lgan tizim soketiga ulanishga majbur qildi va sinov deyarli darhol, administrator huquqlarisiz root huquqiga erishdi va tizim parol faylini o'qidi.
Ikkinchi usul hujumchining soketi bilan root egalik qiladigan soketni almashtirdi va bu ba'zi xizmatlarga qarshi to'g'ridan-to'g'ri root buyrug'ini bajarishga imkon berdi.
Uchinchi usul yo'naltirish qaysi fayllarga kirishi mumkinligini cheklash uchun mo'ljallangan xavfsizlik tekshiruvini tizim fayl yo'lini tekshirgan va uni ishlatgan payt o'rtasida poyga solish orqali yengdi. Bu zanjir laboratoriyada yanada uzoqqa bordi, hisobot aytishicha: u yangi qurilmalarni ro'yxatdan o'tkazish uchun ishlatiladigan kalitni qo'lga kiritdi va shu kalit yordamida hujumchining o'z mashinasini tarmoqqa ishonchli server sifatida qo'shdi.
Bu oxirgi qadam faqat Tailscale'ning Tailnet Lock funksiyasi yoqilmagan tarmoqlarda boshidan oxirigacha ishladi. U yoqilgan tarmoqlarda kerakli sirlar tranzitda qo'lga kiritildi, lekin oxirgi qadam bajarilmadi.
Windisch umumiy natijani "qurtlanadigan" deb tasvirlaydi. Laboratoriyada bitta buzilgan qurilma kirish qoidalari ruxsat beradigan har bir qurilmaga tarqalishi mumkin edi, parollarsiz, o'g'irlangan kalitlarsiz va foydalanuvchi harakatisiz, har bir qadamda bir soniyadan kamroq vaqtda.
Hisobot so'zlari bilan aytganda, "mesh bitta oddiy o'rinni mashina tezligida butun park bo'ylab imtiyozli kirishga aylantiradi." Bu tarqalish laboratoriyada o'lchandi, haqiqiy tarmoqlarda kuzatilmadi.
Hisobot tarqalishni to'xtatgan ikkita narsani nomlaydi: yagona manba-maqsad juftlari sifatida yozilgan kirish qoidalari, ular o'z-o'zidan tarqalishni to'xtatdi, va qurilma kalitlari TPM yoki Secure Enclave kabi apparatga bog'langan.
Hisobotni o'qigan ba'zi tadqiqotchilar "qurtlanadigan" ta'rifini ommaviy ravishda shubha ostiga oldilar, boshqalar esa root huquqiga erishish topilmasini jiddiy deb atadilar.
SSH muammosi hisobotdagi 11 topilmaning biri bo'lib, u Tailscale'ning ilova ulanishlari, serve funksiyasi, qurilmalar o'rtasida ishlatiladigan DERP relay va headscale'ni ham qamrab oladi. Windisch The Hacker News'ga SSH imtiyoz eskalatsiyasi "tashvishli" ekanini, lekin ilova ulanishi topilmasi "ba'zi tashkilotlar uchun yanada ta'sirli bo'lishi mumkin"ligini aytdi. Ilova ulanishi topilmasi, conn25 deb nomlangan eksperimental funksiyada, ruxsat berilgan foydalanuvchiga xavfsizlik jamoasi hech qachon ma'qullamagan manzillarga, jumladan server ma'lumotlarini beradigan bulut provayderining metadata xizmatiga trafik yuborishga imkon beradi.
Barcha topilmalar faqat Windischning hisobotiga tayanadi. Boshqa hech bir tadqiqotchi ularni ommaviy ravishda takrorlamagan va Tailscale aniq texnik da'volarni tasdiqlamagan. Windisch topilmalar ortidagi isbot-kod ommaviy emasligini va uni faqat Tailscale'ning xavfsizlik kontaktiga taqdim etganini aytdi.
Windisch oshkor qilishni "xabar berilgan, lekin muvofiqlashtirilmagan" deb tasvirladi va Ycombinator HN'da shunday yozdi, u yerda kamida bitta sharhlovchi avval Tailscale'ga xabar bermasdan nashr etishni mas'uliyatsiz deb atadi.
The Hacker News'dan savollarga javoban Windisch aslida ommaviy postdan oldin, shanba kuni oldin Tailscale'ga hisobot va isbot-kod nusxasini kompaniyaning xavfsizlik kontaktiga yuborganini aytdi. U shuningdek kompaniya bosh direktori bilan Tailscale arxitekturasi haqidagi xavotirlarini ko'targanini, fayl xeshini ommaviy e'lon qilganini va foydalanuvchilarga Tailscale SSH'ni o'chirishni maslahat berganini aytdi.
Hisobot Tailscale'ning shu qismidagi muammolar ketma-ketligining eng so'nggisi. 2026-yil boshida kompaniya Tailscale SSH va server soket ishlov berish kamchiliklarini, jumladan SSH Unix soket yo'naltirishi imtiyozli soketga yetishi mumkin bo'lgan birini, 1.98.9 versiyasida tuzatdi.
Hozir Nima Qilish Kerak
Yamoq yo'qligi sababli, mavjud choralar Tailscale SSH va tegishli funksiyalarni qanday sozlashni o'zgartirishdan iborat. Hisobot va Tailscale'ning o'z maslahatlari ularning aksariyatida bir-biriga mos keladi.
- Tailscale SSH kirish qoidalarini ko'rib chiqing. Ularni bitta qurilma va bitta maqsadni nomlaydigan yagona manba-maqsad juftlari sifatida yozing va identifikator yoki teg bo'yicha keng ruxsat beradigan keng qoidalarni olib tashlang. Hisobot per-juft qoidalarni sinovda tarqalishni to'xtatgan yagona nazorat deb ataydi.
- SSH port yo'naltirishni mumkin bo'lgan joyda o'chiring. Tailscale'ning xostlangan xizmatida bu har bir qoida sozlamasi. Headscale 0.29.5 versiyasida uni o'chirib bo'lmaydi, shuning uchun u yerdagi har bir SSH ruxsatini maqsadda root berish deb qarang.
- Kerak bo'lmagan qurilmalardan ilova ulanish ruxsatlarini olib tashlang.
- Unix soketiga ishora qiladigan har qanday tailscale serve forward'ni olib tashlang.
- Tugun kalitining amal qilish muddatini yoqing, shunda o'g'irlangan qurilma kaliti abadiy amal qilmaydi.
- Agar qurilma buzilgan bo'lsa, uni nazorat tekisligida o'chiring. Mashinani qayta tasvirlash hujumchi allaqachon nusxa olgan kalitlarni bekor qilmaydi.
Tailscale shuningdek SSH tekshiruv rejimini yoqishni, bu sessiya boshlanishidan oldin kirish qadamini qo'shadi, va avtomatik yangilanishlarni yoqishni tavsiya qiladi. Tekshiruv rejimi imtiyoz eskalatsiyasini tuzatmaydi. U faqat uning oldiga yana bir to'siq qo'yadi.
A single hacked device on a Tailscale network can be used to gain root access to other servers it can reach, according to a security researcher who published the findings this week.
The attack requires two things: Tailscale SSH set up to allow port forwarding, and an attacker who already controls one device that the network's access rules permit to connect to the target.
The findings were published on October 25 in a report called Tailworm by Erica Windisch of Cyberdione Labs. Windisch tested Tailscale version 1.104.2 and headscale version 0.29.5, the self-hosted server some networks use to run Tailscale instead of the company's hosted service, over three days in a lab.
The report describes tests on that software, not attacks against real networks. As of publication, Tailscale had issued no security bulletin, no CVE identifier, and no fixed version.
Tailscale has responded in public. Mike Shaver, the company's vice president of engineering, wrote on Reddit that Tailscale had received the report, had already been looking at the same areas with outside security specialists, and had found issues it is working to fix. Shaver said the company is still working out which setups are affected, and that it is "not recommending that everyone disable Tailscale SSH."
Tailscale SSH does not work like a normal SSH server. Rather than checking a connecting user's password or key, it identifies the device, and a single access rule decides whether that device may open an SSH session to a target.
Because of this, the attack needs no stolen passwords or keys. It needs a foothold on one device first, which the report says an attacker can get the usual ways: a vulnerable web application, a poisoned software package, phishing, or stolen login details. Tailscale does not create that first foothold.
How much an administrator can do about it depends on where the network is run. On Tailscale's hosted service, forwarding can be switched off per rule. On headscale version 0.29.5, forwarding cannot be turned off at all. The report says every SSH grant there should therefore be treated as giving root on the target.
In the lab, Windisch showed the problem in stages. Using standard SSH port forwarding, an ordinary session caused the root-level Tailscale process to connect to a system socket that only root should access, and the test gained root and read the system password file almost immediately, without administrator rights.
A second method replaced a root-owned socket with the attacker's, allowing direct root command execution against certain services.
A third method defeated a safety check meant to limit which files forwarding can access by racing the system between when it checks a file path and when it uses it. That chain went further in the lab, the report says: it captured a key used to enroll new devices and used the key to join an attacker's own machine to the network as a trusted server.
That last step worked from start to finish only on networks where Tailscale's Tailnet Lock feature was not enabled. On networks that do, the needed secrets were captured in transit, but the final step was not completed.
Windisch describes the overall result as "wormable." In the lab, one compromised device could spread to every device that the access rules allow, with no passwords, no stolen keys, and no user action, in under a second per step.
In the report's words, "the mesh converts one ordinary foothold into fleet-wide privileged access at machine speed." That spread was measured in a lab, not seen on real networks.
The report names two things that held it back: access rules written as single source-to-destination pairs, which stopped the spread on their own, and device keys tied to hardware such as a TPM or Secure Enclave.
Some researchers who read the report have publicly questioned the "wormable" description, while others have called the root-access finding serious.
The SSH problem is one of 11 findings in the report, which also covers Tailscale's app connectors, its serve feature, the DERP relay used between devices, and headscale. Windisch told The Hacker News that the SSH privilege escalation "is worrying," but that the app connector finding "may be more impactful to some organizations." The app connector finding, in an experimental feature called conn25, lets a permitted user send traffic to destinations the security team never approved, including a cloud provider's metadata service, which can hand out server credentials.
All of the findings rest on Windisch's report alone. No other researcher has publicly reproduced them, and Tailscale has not confirmed the specific technical claims. Windisch said the proof-of-concept code behind the findings is not public, and that she provided it only to Tailscale's security contact.
Windisch has described the disclosure as "reported but not coordinated," writing as much on Ycombinator HN, and at least one commenter there called publishing without first reporting to Tailscale irresponsible.
In response to questions from The Hacker News, Windisch said she had in fact given Tailscale a copy of the report and the proof-of-concept code before the public post, sending them to the company's security contact on the Saturday beforehand. She said she had also raised concerns about Tailscale's architecture with the company's chief executive earlier, and had publicly posted a file hash and advised users to disable Tailscale SSH.
The report is the latest in a run of problems in the same part of Tailscale. Earlier in 2026, the company fixed several Tailscale SSH and server socket-handling flaws, including one where SSH Unix socket forwarding could reach a privileged socket, in version 1.98.9.
What to Do Now
Because there is no patch, the available steps are changes to how Tailscale SSH and related features are set up. The report and Tailscale's own advice overlap on most of them.
- Review your Tailscale SSH access rules. Write them as single source-to-destination pairs that name one device and one target, and remove broad rules that grant access by identity or tag. The report calls per-pair rules the one control that stopped the spread in testing.
- Turn off SSH port forwarding where you can. On Tailscale's hosted service this is a per-rule setting. On headscale version 0.29.5 it cannot be turned off, so treat every SSH grant there as giving root on the target.
- Remove app connector permissions from devices that do not need them.
- Remove any tailscale serve forward that points at a Unix socket.
- Turn on node-key expiry, so a stolen device key does not stay valid forever.
- If a device is compromised, delete it at the control plane. Reimaging the machine does not revoke keys an attacker may have already copied off it.
Tailscale also suggests enabling SSH check mode, which adds a login step before a session starts, and enabling automatic updates. Check mode does not fix the privilege escalation. It only adds another barrier in front of it.
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