CVE-2026-22998 — nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_pdu_iovec
In the Linux kernel, the following vulnerability has been resolved: nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_pdu_iovec Commit efa56305908b ("nvmet-tcp: Fix a kernel panic when host sends an invalid H2C PDU length") added ttag bounds checking and data_offset validation in nvmet_tcp_handle_h2c_data_pdu(), but it did not validate whether the command's data structures (cmd->req.sg and cmd->iov) have been properly initialized before processing H2C_DATA PDUs. The nvmet_tcp_build_pdu_iovec() function dereferences these pointers without NULL checks. This can be triggered by sending H2C_DATA PDU immediately after the ICREQ/ICRESP handshake, before sending a CONNECT command or NVMe write command. Attack vectors that trigger NULL pointer dereferences: 1. H2C_DATA PDU sent before CONNECT → both pointers NULL 2. H2C_DATA PDU for READ command → cmd->req.sg allocated, cmd->iov NULL 3. H2C_DATA PDU for uninitialized command slot → both pointers NULL The fix validates both cmd->req.sg and cmd->iov before calling nvmet_tcp_build_pdu_iovec(). Both checks are required because: - Uninitialized commands: both NULL - READ commands: cmd->req.sg allocated, cmd->iov NULL - WRITE commands: both allocated
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 0.8% (30-day exploitation probability)+8
- Technical severity (high)+6
- Automatable exploitation (SSVC)+3
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.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
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, Linux Linux Kernel).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (memory corruption), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Linux | Linux |
≥ 2871aa407007f6f531fae181ad252486e022df42 and < 7d75570002929d20e40110d6b03e46202c9d1bc7version 6.8≥ 6.7.2 and < 6.8≥ 5.4.268 and < 5.5≥ 6.6.14 and < 6.6.122≥ 6.1.75 and < 6.1.162≥ 5.15.148 and < 5.15.199≥ 5.10.209 and < 5.10.249 and 8 moreversion 70154e8d015c9b4fb56c1a2ef1fc8b83d45c7f68version ee5e7632e981673f42a50ade25e71e612e543d9d≥ efa56305908ba20de2104f1b8508c6a7401833be and < 32b63acd78f577b332d976aa06b56e70d054cbba≥ efa56305908ba20de2104f1b8508c6a7401833be and < 374b095e265fa27465f34780e0eb162ff1bef913≥ efa56305908ba20de2104f1b8508c6a7401833be and < 3def5243150716be86599c2a1767c29c68838b6d≥ 24e05760186dc070d3db190ca61efdbce23afc88 and < fdecd3b6aac10d5a18d0dc500fe57f8648b66cd4≥ 4cb3cf7177ae3666be7fb27d4ad4d72a295fb02d and < 76abc83a9d25593c2b7613c549413079c14a4686≥ f775f2621c2ac5cc3a0b3a64665dad4fb146e510 and < baabe43a0edefac8cd7b981ff87f967f6034dafe |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
≥ 5.4.268 and < 5.5version 6.19-rc5version 6.19-rc4version 6.19-rc3version 6.19-rc2version 6.19-rc1≥ 6.13 and < 6.18.7≥ 6.7.2 and < 6.12.67 and 4 more≥ 6.6.14 and < 6.6.122≥ 6.1.75 and < 6.1.162≥ 5.15.148 and < 5.15.199≥ 5.10.209 and < 5.10.249 |
Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | 3.9 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.5 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.79%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 7.5
- Source status changed · → Modified
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
7 on the record
- git.kernel.org/stable/c/3def5243150716be86599c2a1767c29c68838b6d
- git.kernel.org/stable/c/76abc83a9d25593c2b7613c549413079c14a4686
- git.kernel.org/stable/c/baabe43a0edefac8cd7b981ff87f967f6034dafe
- git.kernel.org/stable/c/374b095e265fa27465f34780e0eb162ff1bef913
- git.kernel.org/stable/c/32b63acd78f577b332d976aa06b56e70d054cbba
- git.kernel.org/stable/c/7d75570002929d20e40110d6b03e46202c9d1bc7
- git.kernel.org/stable/c/fdecd3b6aac10d5a18d0dc500fe57f8648b66cd4
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 9h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 9h
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
- Unknown CVE-2026-98431 RDMA/uverbs: Fix mmap_lock/disassociation_lock circular dependency 1d
- Unknown CVE-2026-98430 RDMA/efa: Keep admin queues alive while IRQ is registered 1d
- Unknown CVE-2026-98429 RDMA/efa: Keep EQ resources alive while IRQ is registered 1d
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 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-2026-22998 is "nvme-tcp: fix NULL pointer dereferences in nvmet_tcp_build_pdu_iovec", rated High. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 7.5 describes technical severity. EPSS 0.79% 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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