VulnerabilityPublished 18 Oct 2026Updated 21 Oct 2026

CVE-2026-98850: Linux kernel · net/packet: prevent TX_RING byte count overflow

Affects Linux kernelSource CVE Database V5

Not known to be exploited · fixed in be12b221c0301111eeb023be04add3c6ad7c21fe : update Linux kernel when convenient.

Data as of 26 Oct 2026, 13:07 UTC

Severity

Unrated

Rated by Threat Radar · CVSS not yet scored by NVD

EPSS: 0.1% chance of exploitation in 30 days – higher than 4% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in be12b221c0301111eeb023be04add3c6ad7c21fe, ae169d318d5d23bac76ece90a7e2b5cb760ed043, 69ca64bbb528898916f309552053c32a04a36ebc +2

Exploitation evidence

Disclosed: evidence found.
CVE published 18 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade to a fixed release listed under Affected software.

Affected software

Product	Affected	Fixed in
LinuxLinux	Affected ≥ 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1, < be12b221c0301111eeb023be04add3c6ad7c21fe	Fixed in be12b221c0301111eeb023be04add3c6ad7c21fe
LinuxLinux	Affected ≥ 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1, < ae169d318d5d23bac76ece90a7e2b5cb760ed043	Fixed in ae169d318d5d23bac76ece90a7e2b5cb760ed043
LinuxLinux	Affected ≥ 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1, < 69ca64bbb528898916f309552053c32a04a36ebc	Fixed in 69ca64bbb528898916f309552053c32a04a36ebc
LinuxLinux	Affected ≥ 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1, < 9fd63d284e251332f4874ef9023cde472f315f86	Fixed in 9fd63d284e251332f4874ef9023cde472f315f86
LinuxLinux	Affected ≥ 69e3c75f4d541a6eb151b3ef91f34033cb3ad6e1, < 2cf81fc9505b148b1b70068303ea6ea4b1212403	Fixed in 2cf81fc9505b148b1b70068303ea6ea4b1212403
LinuxLinux	Affected =2.6.31	Fixed in–

Description

In the Linux kernel, the following vulnerability has been resolved: net/packet: prevent TX_RING byte count overflow tpacket_snd() drains every SEND_REQUEST frame in a TX ring and adds each valid packet length to the signed int len_sum. Userspace can recycle completed frames concurrently, so a single blocking send call is not bounded by the ring size. After enough successful transmissions len_sum wraps into the negative range. In particular, 65536 65535-byte frames followed by a 65007-byte frame produce 0xfffffdef, or -EIOCBQUEUED. sock_sendmsg_nosec() treats that as an impossible return and triggers a BUG. On systems configured to panic on oops, a CAP_NET_RAW holder can panic the host kernel. Stop before the next frame would make the byte count exceed INT_MAX. The positive short count leaves that frame pending for a later send call. A two-thread TPACKET_V2 reproducer triggered the BUG on an arm64 build of Linux 7.3-rc4. With this change, the same reproducer returned the expected positive short count without an oops.

References

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