Red Hat Security Advisory: gvisor-tap-vsock security update
Affects Red Hat gvisor-tap-vsockSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.5 High · fixed in Red Hat package updates : patch Red Hat asn1 soon.
Data as of 11 Nov 2026, 13:27 UTC
Thin evidence
One scorer or none| CISA-ADP | CVSS 3.1 | 7.5 |
|---|
- Patch
- Available – fixed in 1.27.0-rc.3, 1.26.6, 1.25.13
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 13 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.
What to do
Upgrade encoding/asn1 to 1.27.0-rc.3, 1.26.6 or 1.25.13.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Go standard libraryencoding/asn1 | Affected
| Fixed in
|
| Go standard libraryencoding/asn1 | Affected
| Fixed in
|
| Go standard libraryencoding/asn1 | Affected
| Fixed in
|
Goencoding/asn1pkg:golang/encoding/asn1Other threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released updated gvisor-tap-vsock packages for Red Hat Enterprise Linux 9 on multiple architectures that address these vulnerabilities. Users should apply the security update as detailed in the Red Hat advisory (RHSA-2026:98502) to remediate these issues. No additional mitigations are specified or required beyond applying the official patches.
Description
Red Hat has issued a security update for gvisor-tap-vsock, a Go-based replacement for libslirp and VPNKit. The update addresses multiple denial of service vulnerabilities and a man-in-the-middle vulnerability in various Go libraries used by gvisor-tap-vsock. These include excessive recursion in ASN.1 unmarshalling, unencrypted HTTP/2 connection issues, indefinite TLS KeyUpdate messages, crafted HTTP Range headers, multiple ECH outer extension references, memory limit bypass in multipart form parsing, and untrusted intermediate certificates allowing man-in-the-middle attacks. The update is rated as Important by Red Hat and affects Red Hat Enterprise Linux 9 on multiple architectures.
References
- access.redhat.com/errata/RHSA-2026:98502 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2515815 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2515827 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2515839 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2548334 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2548336 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2548341 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2556068 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_98502.json (opens in a new tab)