Vulnerabilities

Vulnerability · CVE-2026-31636

In the Linux kernel, the following vulnerability has been resolved: rxrpc: fix RESPONSE authenticator parser OOB read rxgk_verify_authenticator() copies auth_len bytes…

Published Apr 24, 2026 · catalog updated Jun 17, 2026 · linux kernel

Check if you run it

No confirmed exploitation is on record for CVE-2026-31636. EPSS is 0.44%. Act only if a listed version of linux kernel is installed.

Gaps on this record

  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Critical9.1
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.44%
Remediation
Advisory link
Affected products
cpe linux/linux kernel

In the Linux kernel, the following vulnerability has been resolved: rxrpc: fix RESPONSE authenticator parser OOB read rxgk_verify_authenticator() copies auth_len bytes into a temporary buffer and then passes p + auth_len as the parser limit to rxgk_do_verify_authenticator(). Since p is a __be32 *, that inflates the parser end pointer by a factor of four and lets malformed RESPONSE authenticators read past the kmalloc() buffer. Decoded from the original latest-net reproduction logs with scripts/decode_stacktrace.sh: BUG: KASAN: slab-out-of-bounds in rxgk_verify_response() Call Trace: dump_stack_lvl() [lib/dump_stack.c:123] print_report() [mm/kasan/report.c:379 mm/kasan/report.c:482] kasan_report() [mm/kasan/report.c:597] rxgk_verify_response() [net/rxrpc/rxgk.c:1103 net/rxrpc/rxgk.c:1167 net/rxrpc/rxgk.c:1274] rxrpc_process_connection() [net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364 net/rxrpc/conn_event.c:386] process_one_work() [kernel/workqueue.c:3281] worker_thread() [kernel/workqueue.c:3353 kernel/workqueue.c:3440] kthread() [kernel/kthread.c:436] ret_from_fork() [arch/x86/kernel/process.c:164] Allocated by task 54: rxgk_verify_response() [include/linux/slab.h:954 net/rxrpc/rxgk.c:1155 net/rxrpc/rxgk.c:1274] rxrpc_process_connection() [net/rxrpc/conn_event.c:266 net/rxrpc/conn_event.c:364 net/rxrpc/conn_event.c:386] Convert the byte count to __be32 units before constructing the parser limit.

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  • cpe linux/linux kernel6.16
  • cpe linux/linux kernel7.0

How to fix CVE-2026-31636

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-31636. EPSS is 0.44%. Act only if a listed version of linux kernel is installed.

Which versions are affected?

Compare what you have installed with linux/linux kernel 6.16; linux/linux kernel 7.0. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-125: Out-of-bounds Read. EPSS 0.44%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Apr 24, 2026 · NIST NVD

    Detected

    In the Linux kernel, the following vulnerability has been resolved: rxrpc: fix RESPONSE authenticator parser OOB read rxgk_verify_authenticator() copies auth_len bytes into a temporary buffer and then passes p + auth_len as the parser limit to rxgk_do_verify_authenticator(). Since p is a __be32 *, that inflates the parser end pointer by a factor of four and lets malformed RESPONSE authenticators r

  2. Jun 17, 2026 · NIST NVD

    Updated

    In the Linux kernel, the following vulnerability has been resolved: rxrpc: fix RESPONSE authenticator parser OOB read rxgk_verify_authenticator() copies auth_len bytes into a temporary buffer and then passes p + auth_len as the parser limit to rxgk_do_verify_authenticator(). Since p is a __be32 *, that inflates the parser end pointer by a factor of four and lets malformed RESPONSE authenticators r

Sources

  • CVE.orgVulnerability recordCVE-2026-31636

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-31636

    30-day exploitation probability 0.4%

    first.org
  • NIST NVDVulnerability recordCVE-2026-31636

    In the Linux kernel, the following vulnerability has been resolved: rxrpc: fix RESPONSE authenticator parser OOB read rxgk_verify_authenticator() copies auth_len bytes into a temporary buffer and then passes p + auth_len as the parser limit to rxgk_do_verify_authenticator(). Si

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.