CVE-2026-98969 — net/sched: em_text: reject unterminated algo before autoload
In the Linux kernel, the following vulnerability has been resolved: net/sched: em_text: reject unterminated algo before autoload This is a follow-up to commit 9c572a83037a ("net/sched: fix potential stack infoleak in em_text_dump()"), which zero-initialised the dump-side struct. Sashiko pointed at a pre-existing bug that exposed the change-side input-validation gap open. em_text_change() casts the raw netlink attribute payload to struct tcf_em_text and passes conf->algo, a 16-byte array with no enforced NUL terminator, to textsearch_prepare(). On the TS_AUTOLOAD retry textsearch_prepare() calls request_module("ts_%s", algo); vsnprintf() walks %s until it finds a NUL, so an algo[] with no NUL reads past the array into the adjacent struct fields and payload and feeds those bytes to the usermode helper command line. This is an out-of-bounds read and a kernel memory disclosure. Reject the attribute when no NUL exists within TC_EM_TEXT_ALGOSIZ bytes, matching the check xt_string has had since 3ab720881b6e. Conditions to recreate the bug: - CAP_NET_ADMIN on the target netns (namespace-local via unshare -Urn is enough) - install clsact on an interface, then add a basic filter with one text ematch whose algo[] is 16 bytes with no NUL (e.g. "A"*16) and pattern_len at least 1 - the add fails with -ENOENT and the kernel invokes modprobe with a module name made of "ts_" plus the 16 bytes and the adjacent payload
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ d675c989ed2d4ba23dff615330b04371aea83534 and < 00bcc303000bac524d62eed054d77372b38ace0f≥ d675c989ed2d4ba23dff615330b04371aea83534 and < 22182f91c6703af6e9832cffe6d22b381031cb5a≥ d675c989ed2d4ba23dff615330b04371aea83534 and < 85e5512369d4fe6e5f2c43712d9f9e01d4ae8437≥ d675c989ed2d4ba23dff615330b04371aea83534 and < b627c6ba20be20334338229b4820baacb9d96826≥ d675c989ed2d4ba23dff615330b04371aea83534 and < c9728fcf2e7fb4a7a8d08ebd9524c3b02ae1a021version 2.6.13≥ d675c989ed2d4ba23dff615330b04371aea83534 and < 64153f1dd14dabfd4e79bf506bb5b5d66f7b42eb≥ d675c989ed2d4ba23dff615330b04371aea83534 and < b62fb105961b677418cbc0a0a8837a41735729ec and 1 more≥ d675c989ed2d4ba23dff615330b04371aea83534 and < b4da5c85cd701066ff429727fb61b84bde8bcce2 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 24, 2026 → Oct 30, 2026 · 7 reading(s) · max 0.21%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Not enough vector or weakness data: use the affected application’s logs as a starting point.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 3× References added · Oct 23, 2026 – Oct 30, 2026
- 1× Official description updated · Oct 23, 2026 – Oct 23, 2026
References
10 on the record
- git.kernel.org/stable/c/00bcc303000bac524d62eed054d77372b38ace0f
- git.kernel.org/stable/c/22182f91c6703af6e9832cffe6d22b381031cb5a
- git.kernel.org/stable/c/b627c6ba20be20334338229b4820baacb9d96826
- git.kernel.org/stable/c/c9728fcf2e7fb4a7a8d08ebd9524c3b02ae1a021
- git.kernel.org/stable/c/85e5512369d4fe6e5f2c43712d9f9e01d4ae8437
- git.kernel.org/stable/c/b4da5c85cd701066ff429727fb61b84bde8bcce2
- git.kernel.org/stable/c/64153f1dd14dabfd4e79bf506bb5b5d66f7b42eb
- github.com/advisories/GHSA-g75r-rwjf-jp26
- nvd.nist.gov/vuln/detail/CVE-2026-98969
- git.kernel.org/stable/c/b62fb105961b677418cbc0a0a8837a41735729ec
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2d
- Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2d
- Unknown CVE-2026-99207 scsi: target: Disable interrupts while holding delayed_cmd_lock 2d
- Unknown CVE-2026-99208 drm/xe/oa: Zero OA buffer at allocation 2d
- Unknown CVE-2026-99209 drm/xe: skip eviction of a BO with no resource 2d
- Unknown CVE-2026-99210 accel/rocket: clear rdev on device init failure 2d
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No CVSS score published by NVD, the CNA, CISA or GitHub so far.
- No fixed version, patch or mitigation documented.
- No CISA SSVC assessment.
- No CWE classification.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-98969 is "net/sched: em_text: reject unterminated algo before autoload", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.17% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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