CVE-2026-45905

MEDIUMNVD 4.74.7
EchelonGraph scoreMEDIUM confidence

Score 4.7 from GitHub Security Advisory published 2026-05-27. NVD baseline CVSS 4.7; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 4 sources updated this week
4.7EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 4.7Exploit: None knownExposed: 0

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path

icmp_route_lookup() performs multiple route lookups to find a suitable route for sending ICMP error messages, with special handling for XFRM (IPsec) policies.

The lookup sequence is:

  • First, lookup output route for ICMP reply (dst = original src)
  • Pass through xfrm_lookup() for policy check
  • If blocked (-EPERM) or dst is not local, enter "reverse path"
  • In reverse path, call xfrm_decode_session_reverse() to get fl4_dec
which reverses the original packet's flow (saddr<->daddr swapped)
  • If fl4_dec.saddr is local (we are the original destination), use
__ip_route_output_key() for output route lookup
  • If fl4_dec.saddr is NOT local (we are a forwarding node), use
ip_route_input() to simulate the reverse packet's input path
  • Finally, pass rt2 through xfrm_lookup() with XFRM_LOOKUP_ICMP flag

The bug occurs in step 6: ip_route_input() is called with fl4_dec.daddr (original packet's source) as destination. If this address becomes local between the initial check and ip_route_input() call (e.g., due to concurrent "ip addr add"), ip_route_input() returns a LOCAL route with dst.output set to ip_rt_bug.

This route is then used for ICMP output, causing dst_output() to call ip_rt_bug(), triggering a WARN_ON:

------------[ cut here ]------------ WARNING: net/ipv4/route.c:1275 at ip_rt_bug+0x21/0x30, CPU#1 Call Trace: ip_push_pending_frames+0x202/0x240 icmp_push_reply+0x30d/0x430 __icmp_send+0x1149/0x24f0 ip_options_compile+0xa2/0xd0 ip_rcv_finish_core+0x829/0x1950 ip_rcv+0x2d7/0x420 __netif_receive_skb_one_core+0x185/0x1f0 netif_receive_skb+0x90/0x450 tun_get_user+0x3413/0x3fb0 tun_chr_write_iter+0xe4/0x220 ...

Fix this by checking rt2->rt_type after ip_route_input(). If it's RTN_LOCAL, the route cannot be used for output, so treat it as an error.

The reproducer requires kernel modification to widen the race window, making it unsuitable as a selftest. It is available at:

https://gist.github.com/mrpre/eae853b72ac6a750f5d45d64ddac1e81

CVSS v3
4.7
EG Score
4.7(medium)
EG Risk
26(Track)
EG Risk 26/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity47% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
2%
KEV
Not listed

Published

May 27, 2026

Last Modified

June 24, 2026

Advisory Details (6)

Auto-updated Jun 24, 2026
No patch confirmed yet.
generic

xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/b04061f89ffc6168e7ec3c71d0086ec3c3797228
generic

xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/9a95ec9144eeff1fc6fbcc21b677e322c6f1430b
generic

xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/81b84de32bb27ae1ae2eb9acf0420e9d0d14bf00
generic

xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/423ce12d10b426709489d6b84fdaa6d2f31c5652
generic

xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/2c1f59005da9dd4b07b26984fd719e36557dc57c
generic

xfrm: fix ip_rt_bug race in icmp_route_lookup reverse path - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/1c9ef28f643cce34a6a6c36c8f4d6d60a60db7e1

Vendor Advisories for CVE-2026-45905(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(13)

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 7.2~rc5-1~exp1 (496 versions)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (48 versions)6.1.170-1
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.85-1~bpo12+1 (17 versions)6.12.85-1
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.18~rc7-1~exp1 (103 versions)6.18.14-1

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(12)

Data Freshness Timeline

(refreshed 7× in last 7d / 30× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 199 total refreshes for this CVE.

  1. 2026-09-18 19:28 UTCEPSS rescore
  2. 2026-09-17 19:31 UTCEPSS rescore
  3. 2026-09-16 14:08 UTCEPSS rescore
  4. 2026-09-16 05:15 UTCEPSS rescore
  5. 2026-09-14 09:06 UTCEG score recompute
  6. 2026-09-14 09:06 UTCVendor advisory
  7. 2026-09-14 09:06 UTCGHSA enrichment
  8. 2026-09-13 16:47 UTCEPSS rescore
  9. 2026-09-13 04:09 UTCOSV refresh
  10. 2026-09-12 15:01 UTCEPSS rescore
  11. 2026-09-11 14:53 UTCEPSS rescore
  12. 2026-09-11 09:37 UTCEPSS rescore
  13. 2026-09-10 09:34 UTCEPSS rescore
  14. 2026-09-08 22:00 UTCEPSS rescore
  15. 2026-09-06 13:47 UTCEPSS rescore
  16. 2026-09-04 05:06 UTCEPSS rescore
  17. 2026-09-02 14:12 UTCEPSS rescore
  18. 2026-09-01 13:54 UTCEPSS rescore
  19. 2026-08-30 19:17 UTCEPSS rescore
  20. 2026-08-28 21:41 UTCEPSS rescore
  21. 2026-08-27 14:25 UTCEPSS rescore
  22. 2026-08-26 14:46 UTCEPSS rescore
  23. 2026-08-25 13:49 UTCEPSS rescore
  24. 2026-08-25 05:44 UTCEG score recompute
  25. 2026-08-25 05:44 UTCVendor advisory
Show 75 more
  1. 2026-08-25 05:44 UTCGHSA enrichment
  2. 2026-08-23 15:32 UTCEG score recompute
  3. 2026-08-23 15:32 UTCVendor advisory
  4. 2026-08-23 15:32 UTCGHSA enrichment
  5. 2026-08-23 00:19 UTCEPSS rescore
  6. 2026-08-21 23:49 UTCEPSS rescore
  7. 2026-08-21 20:52 UTCEG score recompute
  8. 2026-08-21 20:52 UTCVendor advisory
  9. 2026-08-21 20:52 UTCGHSA enrichment
  10. 2026-08-20 22:55 UTCEPSS rescore
  11. 2026-08-20 17:41 UTCEG score recompute
  12. 2026-08-20 17:41 UTCVendor advisory
  13. 2026-08-20 17:41 UTCGHSA enrichment
  14. 2026-08-19 17:04 UTCEPSS rescore
  15. 2026-08-18 13:48 UTCEPSS rescore
  16. 2026-08-17 13:47 UTCEPSS rescore
  17. 2026-08-17 09:21 UTCEG score recompute
  18. 2026-08-17 09:21 UTCVendor advisory
  19. 2026-08-17 09:21 UTCGHSA enrichment
  20. 2026-08-16 14:56 UTCEPSS rescore
  21. 2026-08-16 02:57 UTCEG score recompute
  22. 2026-08-16 02:57 UTCVendor advisory
  23. 2026-08-16 02:57 UTCGHSA enrichment
  24. 2026-08-16 02:14 UTCEPSS rescore
  25. 2026-08-15 02:24 UTCEG score recompute
  26. 2026-08-15 02:24 UTCVendor advisory
  27. 2026-08-15 02:24 UTCGHSA enrichment
  28. 2026-08-15 01:30 UTCEPSS rescore
  29. 2026-08-14 01:52 UTCEG score recompute
  30. 2026-08-14 01:52 UTCVendor advisory
  31. 2026-08-14 01:52 UTCGHSA enrichment
  32. 2026-08-13 22:00 UTCEPSS rescore
  33. 2026-08-13 01:19 UTCEG score recompute
  34. 2026-08-13 01:19 UTCVendor advisory
  35. 2026-08-13 01:19 UTCGHSA enrichment
  36. 2026-08-12 13:51 UTCEPSS rescore
  37. 2026-08-12 00:47 UTCVendor advisory
  38. 2026-08-12 00:47 UTCGHSA enrichment
  39. 2026-08-11 00:15 UTCEG score recompute
  40. 2026-08-11 00:15 UTCVendor advisory
  41. 2026-08-11 00:15 UTCGHSA enrichment
  42. 2026-08-11 00:00 UTCEPSS rescore
  43. 2026-08-09 23:06 UTCEG score recompute
  44. 2026-08-09 23:06 UTCVendor advisory
  45. 2026-08-09 23:06 UTCGHSA enrichment
  46. 2026-08-09 13:46 UTCEPSS rescore
  47. 2026-08-08 22:34 UTCEG score recompute
  48. 2026-08-08 22:34 UTCVendor advisory
  49. 2026-08-08 22:34 UTCGHSA enrichment
  50. 2026-08-08 16:37 UTCEPSS rescore
  51. 2026-08-07 22:00 UTCEG score recompute
  52. 2026-08-07 22:00 UTCVendor advisory
  53. 2026-08-07 22:00 UTCGHSA enrichment
  54. 2026-08-06 21:28 UTCEG score recompute
  55. 2026-08-06 21:28 UTCVendor advisory
  56. 2026-08-06 21:28 UTCGHSA enrichment
  57. 2026-08-06 13:47 UTCEPSS rescore
  58. 2026-08-05 20:55 UTCEG score recompute
  59. 2026-08-05 20:55 UTCVendor advisory
  60. 2026-08-05 20:55 UTCGHSA enrichment
  61. 2026-08-05 19:17 UTCEPSS rescore
  62. 2026-08-04 15:10 UTCEPSS rescore
  63. 2026-08-04 10:39 UTCEPSS rescore
  64. 2026-08-03 16:49 UTCEG score recompute
  65. 2026-08-03 16:49 UTCVendor advisory
  66. 2026-08-03 16:49 UTCGHSA enrichment
  67. 2026-08-03 10:36 UTCEPSS rescore
  68. 2026-08-02 16:16 UTCEG score recompute
  69. 2026-08-02 16:16 UTCVendor advisory
  70. 2026-08-02 16:16 UTCGHSA enrichment
  71. 2026-08-02 02:27 UTCEPSS rescore
  72. 2026-08-01 15:43 UTCEG score recompute
  73. 2026-08-01 15:43 UTCVendor advisory
  74. 2026-08-01 15:43 UTCGHSA enrichment
  75. 2026-08-01 04:16 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-45905?
CVE-2026-45905 is a medium vulnerability published on May 27, 2026. In the Linux kernel, the following vulnerability has been resolved: xfrm: fix iprtbug race in icmproutelookup reverse path icmproutelookup() performs multiple route lookups to find a suitable route for sending ICMP error messages, with special handling for XFRM (IPsec) policies. The lookup sequence…
When was CVE-2026-45905 disclosed?
CVE-2026-45905 was first published in the National Vulnerability Database on May 27, 2026, with the most recent update on June 24, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-45905 actively exploited?
CVE-2026-45905 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 98.5% of all scored CVEs.
What is the CVSS score of CVE-2026-45905?
CVE-2026-45905 has a CVSS v3 base score of 4.7 (NVD).
How do I remediate CVE-2026-45905?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-45905, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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