CVE-2026-53078 — bpf: Fix same-register dst/src OOB read and pointer leak in sock_ops
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix same-register dst/src OOB read and pointer leak in sock_ops When a BPF sock_ops program accesses ctx fields with dst_reg == src_reg, the SOCK_OPS_GET_SK() and SOCK_OPS_GET_FIELD() macros fail to zero the destination register in the !fullsock / !locked_tcp_sock path. Both macros borrow a temporary register to check is_fullsock / is_locked_tcp_sock when dst_reg == src_reg, because dst_reg holds the ctx pointer. When the check is false (e.g., TCP_NEW_SYN_RECV state with a request_sock), dst_reg should be zeroed but is not, leaving the stale ctx pointer: - SOCK_OPS_GET_SK: dst_reg retains the ctx pointer, passes NULL checks as PTR_TO_SOCKET_OR_NULL, and can be used as a bogus socket pointer, leading to stack-out-of-bounds access in helpers like bpf_skc_to_tcp6_sock(). - SOCK_OPS_GET_FIELD: dst_reg retains the ctx pointer which the verifier believes is a SCALAR_VALUE, leaking a kernel pointer. Fix both macros by: - Changing JMP_A(1) to JMP_A(2) in the fullsock path to skip the added instruction. - Adding BPF_MOV64_IMM(si->dst_reg, 0) after the temp register restore in the !fullsock path, placed after the restore because dst_reg == src_reg means we need src_reg intact to read ctx->temp.
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 0.1% (30-day exploitation probability)+0
- Technical severity (high)+6
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)
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).
- 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 |
≥ fd09af010788a884de1c39537c288830c3d305db and < 0e6b30657bbc771f38025c828d722b6162428508version 5.9≥ 5.4.61 and < 5.5≥ 5.8.4 and < 5.9≥ 5.7.18 and < 5.8version db7f8c57dbdd31f7e59f8dc8d1e1b38607a320efversion a7e52f7f675046d9ffc5692d815fa67c82fcdbf5version 6e0bc946cbeec538322820786b5fb5200a2216ab and 9 moreversion cd4644d904e1d153d516e73e2e127e7a2fe687e1version 48be3df15aa19c04eadf156c9129293c9a10389f≥ fd09af010788a884de1c39537c288830c3d305db and < 10f86a2a5c91fc4c4d001960f1c21abe52545ef6≥ fd09af010788a884de1c39537c288830c3d305db and < 18e3ffde1822f0b48b1753bf34aa97ce839df1d8≥ fd09af010788a884de1c39537c288830c3d305db and < 22400725de070b787cd6d806c5795370ab46d269≥ fd09af010788a884de1c39537c288830c3d305db and < 2a2c98141e0a75f2d4a7d78b0316c88b3da784ac≥ fd09af010788a884de1c39537c288830c3d305db and < 64eaf4ecda007140ddcdb28e00c48c9c69aaba39≥ fd09af010788a884de1c39537c288830c3d305db and < 4c1c5efd9d1d74743d41ce4e1600501b4feb6827≥ fd09af010788a884de1c39537c288830c3d305db and < db1200ec2c3ddf119d4d9ba67982063df06bbacb |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel |
≥ 5.4.61 and < 5.5version 5.9-rc8version 5.9-rc7version 5.9-rc6version 5.9-rc5version 5.9-rc4version 5.9-rc3version 5.9-rc2 and 4 moreversion 5.9≥ 5.9.1 and < 7.0.10≥ 5.8.4 and < 5.9≥ 5.7.18 and < 5.8 |
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 |
|---|---|---|---|---|---|
| 7.8 | CVSS 3.1 | High | 1.8 | 5.9 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | Linux via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: 416baaa9-dc9f-4396-8d5f-8c081fb06d67) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.12%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
- Correlate service crashes/restarts with inbound traffic; repeated crashes may indicate attempts.
Timeline
What happened to this CVE, newest first.
- 2026
- SSVC assessment updated
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 7.8
- 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
8 on the record
- git.kernel.org/stable/c/18e3ffde1822f0b48b1753bf34aa97ce839df1d8
- git.kernel.org/stable/c/10f86a2a5c91fc4c4d001960f1c21abe52545ef6
- git.kernel.org/stable/c/64eaf4ecda007140ddcdb28e00c48c9c69aaba39
- git.kernel.org/stable/c/2a2c98141e0a75f2d4a7d78b0316c88b3da784ac
- git.kernel.org/stable/c/22400725de070b787cd6d806c5795370ab46d269
- git.kernel.org/stable/c/4c1c5efd9d1d74743d41ce4e1600501b4feb6827
- git.kernel.org/stable/c/db1200ec2c3ddf119d4d9ba67982063df06bbacb
- git.kernel.org/stable/c/0e6b30657bbc771f38025c828d722b6162428508
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 1d
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 1d
- Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 2d
- Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 2d
- Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 2d
- Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 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 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-2026-53078 is "bpf: Fix same-register dst/src OOB read and pointer leak in sock_ops", 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 7.8 describes technical severity. EPSS 0.12% 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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