CVE-2026-23277

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-03-20. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit

teql_master_xmit() calls netdev_start_xmit(skb, slave) to transmit through slave devices, but does not update skb->dev to the slave device beforehand.

When a gretap tunnel is a TEQL slave, the transmit path reaches iptunnel_xmit() which saves dev = skb->dev (still pointing to teql0 master) and later calls iptunnel_xmit_stats(dev, pkt_len). This function does:

get_cpu_ptr(dev->tstats)

Since teql_master_setup() does not set dev->pcpu_stat_type to NETDEV_PCPU_STAT_TSTATS, the core network stack never allocates tstats for teql0, so dev->tstats is NULL. get_cpu_ptr(NULL) computes NULL + __per_cpu_offset[cpu], resulting in a page fault.

BUG: unable to handle page fault for address: ffff8880e6659018 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 68bc067 P4D 68bc067 PUD 0 Oops: Oops: 0002 [#1] SMP KASAN PTI RIP: 0010:iptunnel_xmit (./include/net/ip_tunnels.h:664 net/ipv4/ip_tunnel_core.c:89) Call Trace: ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847) __gre_xmit (net/ipv4/ip_gre.c:478) gre_tap_xmit (net/ipv4/ip_gre.c:779) teql_master_xmit (net/sched/sch_teql.c:319) dev_hard_start_xmit (net/core/dev.c:3887) sch_direct_xmit (net/sched/sch_generic.c:347) __dev_queue_xmit (net/core/dev.c:4802) neigh_direct_output (net/core/neighbour.c:1660) ip_finish_output2 (net/ipv4/ip_output.c:237) __ip_finish_output.part.0 (net/ipv4/ip_output.c:315) ip_mc_output (net/ipv4/ip_output.c:369) ip_send_skb (net/ipv4/ip_output.c:1508) udp_send_skb (net/ipv4/udp.c:1195) udp_sendmsg (net/ipv4/udp.c:1485) inet_sendmsg (net/ipv4/af_inet.c:859) __sys_sendto (net/socket.c:2206)

Fix this by setting skb->dev = slave before calling netdev_start_xmit(), so that tunnel xmit functions see the correct slave device with properly allocated tstats.

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: 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
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
2%
KEV
Not listed

Published

March 20, 2026

Last Modified

July 14, 2026

Advisory Details (10)

Auto-updated Jul 17, 2026
⚠️ Active exploitation confirmed. No patch confirmed yet.
generic🔴 Active Exploitation

SSA-082556

https://cert-portal.siemens.com/productcert/html/ssa-082556.html
generic

SSA-019113

https://cert-portal.siemens.com/productcert/html/ssa-019113.html
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/81a43e8005366f16e629d8c95dfe05beaa8d36a7
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/6b1f563d670162e188a0f2aec39c24b67b106e17
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/59b06d8b9bdb6b64b3c534c18da68bce5ccd31be
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/57c153249143333bbf4ecf927bdf8aa2696ee397
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/383493b9940e3d1b5517424081b3e072e20ec43c
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/21ea283c2750c8307aa35ee832b0951cc993c27d
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0cc0c2e661af418bbf7074179ea5cfffc0a5c466
generic

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/0bad9c86edd22dec4df83c2b29872d66fd8a2ff4

Vendor Advisories for CVE-2026-23277(2)

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

Patch Availability(2)

Vendor / EcosystemFixed in / PatchReleasedSource
linuxKernel @ 5.10.253—osv
linuxKernel @ 6.1.167—osv

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

(5 across 4 ecosystems)
Debian:11(2)
PackageVulnerable rangeFixed inDependents
linux5.10.103-1 ... 5.10.92-2 (53 versions)5.10.257-1—
linux-6.16.1.106-3~deb11u1 ... 6.1.164-1~deb11u1 (16 versions)6.1.170-1~deb11u1—
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 ... 6.19~rc8-1~exp1 (119 versions)6.19.10-1—

Weakness Classification(1)

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

Additional Vendor Advisories

(24)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 7× in last 7d / 46× 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 195 total refreshes for this CVE.

  1. 2026-09-04 05:06 UTCEPSS rescore
  2. 2026-09-02 17:08 UTCOSV refresh
  3. 2026-09-02 14:11 UTCEPSS rescore
  4. 2026-09-01 13:53 UTCEPSS rescore
  5. 2026-09-01 04:39 UTCEPSS rescore
  6. 2026-08-30 19:17 UTCEPSS rescore
  7. 2026-08-30 01:22 UTCEPSS rescore
  8. 2026-08-28 21:41 UTCEPSS rescore
  9. 2026-08-27 14:25 UTCEPSS rescore
  10. 2026-08-26 14:46 UTCEPSS rescore
  11. 2026-08-25 13:48 UTCEPSS rescore
  12. 2026-08-21 23:49 UTCEPSS rescore
  13. 2026-08-20 22:55 UTCEPSS rescore
  14. 2026-08-19 17:03 UTCEPSS rescore
  15. 2026-08-17 13:47 UTCEPSS rescore
  16. 2026-08-16 14:56 UTCEPSS rescore
  17. 2026-08-16 11:03 UTCEG score recompute
  18. 2026-08-16 11:03 UTCVendor advisory
  19. 2026-08-16 11:03 UTCGHSA enrichment
  20. 2026-08-16 02:14 UTCEPSS rescore
  21. 2026-08-15 01:30 UTCEPSS rescore
  22. 2026-08-14 07:14 UTCEG score recompute
  23. 2026-08-14 07:14 UTCVendor advisory
  24. 2026-08-14 07:14 UTCGHSA enrichment
  25. 2026-08-13 22:00 UTCEPSS rescore
Show 75 more
  1. 2026-08-12 21:54 UTCEG score recompute
  2. 2026-08-12 21:54 UTCVendor advisory
  3. 2026-08-12 21:54 UTCGHSA enrichment
  4. 2026-08-12 13:50 UTCEPSS rescore
  5. 2026-08-11 13:42 UTCEPSS rescore
  6. 2026-08-11 08:32 UTCEG score recompute
  7. 2026-08-11 08:32 UTCVendor advisory
  8. 2026-08-11 08:32 UTCGHSA enrichment
  9. 2026-08-11 00:00 UTCEPSS rescore
  10. 2026-08-10 07:30 UTCEG score recompute
  11. 2026-08-10 07:30 UTCVendor advisory
  12. 2026-08-10 07:30 UTCGHSA enrichment
  13. 2026-08-09 13:46 UTCEPSS rescore
  14. 2026-08-09 06:46 UTCEG score recompute
  15. 2026-08-09 06:46 UTCVendor advisory
  16. 2026-08-09 06:46 UTCGHSA enrichment
  17. 2026-08-08 16:37 UTCEPSS rescore
  18. 2026-08-07 17:16 UTCEG score recompute
  19. 2026-08-07 17:16 UTCVendor advisory
  20. 2026-08-07 17:16 UTCGHSA enrichment
  21. 2026-08-06 13:46 UTCEPSS rescore
  22. 2026-08-06 01:28 UTCEG score recompute
  23. 2026-08-06 01:28 UTCVendor advisory
  24. 2026-08-06 01:28 UTCGHSA enrichment
  25. 2026-08-05 19:17 UTCEPSS rescore
  26. 2026-08-04 15:10 UTCEPSS rescore
  27. 2026-08-04 10:38 UTCEPSS rescore
  28. 2026-08-04 00:36 UTCEG score recompute
  29. 2026-08-04 00:36 UTCVendor advisory
  30. 2026-08-04 00:36 UTCGHSA enrichment
  31. 2026-08-03 10:35 UTCEPSS rescore
  32. 2026-08-02 16:13 UTCEG score recompute
  33. 2026-08-02 16:13 UTCVendor advisory
  34. 2026-08-02 16:13 UTCGHSA enrichment
  35. 2026-08-02 02:26 UTCEPSS rescore
  36. 2026-08-01 04:15 UTCEPSS rescore
  37. 2026-07-30 01:30 UTCEPSS rescore
  38. 2026-07-24 14:17 UTCEPSS rescore
  39. 2026-07-23 14:18 UTCEPSS rescore
  40. 2026-07-23 14:18 UTCEPSS rescore
  41. 2026-07-23 03:06 UTCEG score recompute
  42. 2026-07-22 14:08 UTCEPSS rescore
  43. 2026-07-21 15:24 UTCEPSS rescore
  44. 2026-07-21 15:24 UTCEPSS rescore
  45. 2026-07-20 17:08 UTCEPSS rescore
  46. 2026-07-19 14:31 UTCEPSS rescore
  47. 2026-07-19 14:31 UTCEPSS rescore
  48. 2026-07-19 02:29 UTCEPSS rescore
  49. 2026-07-19 02:28 UTCEPSS rescore
  50. 2026-07-18 10:04 UTCEPSS rescore
  51. 2026-07-18 10:04 UTCEPSS rescore
  52. 2026-07-17 07:46 UTCOSV refresh
  53. 2026-07-16 17:03 UTCEPSS rescore
  54. 2026-07-16 17:03 UTCEPSS rescore
  55. 2026-07-15 16:57 UTCEPSS rescore
  56. 2026-07-15 16:57 UTCEPSS rescore
  57. 2026-07-15 02:00 UTCEPSS rescore
  58. 2026-07-15 02:00 UTCEPSS rescore
  59. 2026-07-14 13:19 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  60. 2026-07-14 13:11 UTCMITRE cvelistV5
  61. 2026-07-13 22:30 UTCEPSS rescore
  62. 2026-07-13 06:13 UTCEPSS rescore
  63. 2026-07-13 06:13 UTCEPSS rescore
  64. 2026-07-12 05:46 UTCEPSS rescore
  65. 2026-07-12 05:46 UTCEPSS rescore
  66. 2026-07-11 08:27 UTCEPSS rescore
  67. 2026-07-09 19:10 UTCEPSS rescore
  68. 2026-07-08 15:15 UTCEPSS rescore
  69. 2026-07-08 15:15 UTCEPSS rescore
  70. 2026-07-07 13:46 UTCEPSS rescore
  71. 2026-07-06 16:27 UTCEPSS rescore
  72. 2026-07-06 16:27 UTCEPSS rescore
  73. 2026-07-06 02:23 UTCEPSS rescore
  74. 2026-07-06 02:23 UTCEPSS rescore
  75. 2026-07-05 02:30 UTCEPSS rescore

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-23277?
CVE-2026-23277 is a medium vulnerability published on March 20, 2026. In the Linux kernel, the following vulnerability has been resolved: net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit teqlmasterxmit() calls netdevstartxmit(skb, slave) to transmit through slave devices, but does not update skb->dev to the slave device beforehand.…
When was CVE-2026-23277 disclosed?
CVE-2026-23277 was first published in the National Vulnerability Database on March 20, 2026, with the most recent update on July 14, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-23277 actively exploited?
CVE-2026-23277 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 97.7% of all scored CVEs.
What is the CVSS score of CVE-2026-23277?
CVE-2026-23277 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-23277?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-23277, 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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