High

CVE-2025-38279 — bpf: Do not include stack ptr register in precision backtracking bookkeeping

In the Linux kernel, the following vulnerability has been resolved: bpf: Do not include stack ptr register in precision backtracking bookkeeping Yi Lai reported an issue ([1]) where the following warning appears in kernel dmesg: [ 60.643604] verifier backtracking bug [ 60.643635] WARNING: CPU: 10 PID: 2315 at kernel/bpf/verifier.c:4302 __mark_chain_precision+0x3a6c/0x3e10 [ 60.648428] Modules linked in: bpf_testmod(OE) [ 60.650471] CPU: 10 UID: 0 PID: 2315 Comm: test_progs Tainted: G OE 6.15.0-rc4-gef11287f8289-dirty #327 PREEMPT(full) [ 60.654385] Tainted: [O]=OOT_MODULE, [E]=UNSIGNED_MODULE [ 60.656682] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 60.660475] RIP: 0010:__mark_chain_precision+0x3a6c/0x3e10 [ 60.662814] Code: 5a 30 84 89 ea e8 c4 d9 01 00 80 3d 3e 7d d8 04 00 0f 85 60 fa ff ff c6 05 31 7d d8 04 01 48 c7 c7 00 58 30 84 e8 c4 06 a5 ff <0f> 0b e9 46 fa ff ff 48 ... [ 60.668720] RSP: 0018:ffff888116cc7298 EFLAGS: 00010246 [ 60.671075] RAX: 54d70e82dfd31900 RBX: ffff888115b65e20 RCX: 0000000000000000 [ 60.673659] RDX: 0000000000000001 RSI: 0000000000000004 RDI: 00000000ffffffff [ 60.676241] RBP: 0000000000000400 R08: ffff8881f6f23bd3 R09: 1ffff1103ede477a [ 60.678787] R10: dffffc0000000000 R11: ffffed103ede477b R12: ffff888115b60ae8 [ 60.681420] R13: 1ffff11022b6cbc4 R14: 00000000fffffff2 R15: 0000000000000001 [ 60.684030] FS: 00007fc2aedd80c0(0000) GS:ffff88826fa8a000(0000) knlGS:0000000000000000 [ 60.686837] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 60.689027] CR2: 000056325369e000 CR3: 000000011088b002 CR4: 0000000000370ef0 [ 60.691623] Call Trace: [ 60.692821] <TASK> [ 60.693960] ? __pfx_verbose+0x10/0x10 [ 60.695656] ? __pfx_disasm_kfunc_name+0x10/0x10 [ 60.697495] check_cond_jmp_op+0x16f7/0x39b0 [ 60.699237] do_check+0x58fa/0xab10 ... Further analysis shows the warning is at line 4302 as below: 4294 /* static subprog call instruction, which 4295 * means that we are exiting current subprog, 4296 * so only r1-r5 could be still requested as 4297 * precise, r0 and r6-r10 or any stack slot in 4298 * the current frame should be zero by now 4299 */ 4300 if (bt_reg_mask(bt) & ~BPF_REGMASK_ARGS) { 4301 verbose(env, "BUG regs %x\n", bt_reg_mask(bt)); 4302 WARN_ONCE(1, "verifier backtracking bug"); 4303 return -EFAULT; 4304 } With the below test (also in the next patch): __used __naked static void __bpf_jmp_r10(void) { asm volatile ( "r2 = 2314885393468386424 ll;" "goto +0;" "if r2 <= r10 goto +3;" "if r1 >= -1835016 goto +0;" "if r2 <= 8 goto +0;" "if r3 <= 0 goto +0;" "exit;" ::: __clobber_all); } SEC("?raw_tp") __naked void bpf_jmp_r10(void) { asm volatile ( "r3 = 0 ll;" "call __bpf_jmp_r10;" "r0 = 0;" "exit;" ::: __clobber_all); } The following is the verifier failure log: 0: (18) r3 = 0x0 ; R3_w=0 2: (85) call pc+2 caller: R10=fp0 callee: frame1: R1=ctx() R3_w=0 R10=fp0 5: frame1: R1=ctx() R3_w=0 R10=fp0 ; asm volatile (" \ @ verifier_precision.c:184 5: (18) r2 = 0x20202000256c6c78 ; frame1: R2_w=0x20202000256c6c78 7: (05) goto pc+0 8: (bd) if r2 <= r10 goto pc+3 ; frame1: R2_w=0x20202000256c6c78 R10=fp0 9: (35) if r1 >= 0xffe3fff8 goto pc+0 ; frame1: R1=ctx() 10: (b5) if r2 <= 0x8 goto pc+0 mark_precise: frame1: last_idx 10 first_idx 0 subseq_idx -1 mark_precise: frame1: regs=r2 stack= before 9: (35) if r1 >= 0xffe3fff8 goto pc+0 mark_precise: frame1: regs=r2 stack= before 8: (bd) if r2 <= r10 goto pc+3 mark_preci ---truncated---

Published Jul 10, 2025 · Updated Oct 21, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2
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.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.24%

ahead of 15% of scored CVEs · Oct 27, 2026

Affects

Linux

Linux and 1 more

CVSS base

7.8

High · 2 source(s)

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)

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, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 407958a0e980b9e1842ab87b5a1040521e1e24e9 and < 2d9a8022009d2d6ad7aaea249902d88f1fa70144≥ 407958a0e980b9e1842ab87b5a1040521e1e24e9 and < 4265682c29c92f52c0da6fad5a79b5801462c8de≥ 407958a0e980b9e1842ab87b5a1040521e1e24e9 and < ac49b7560b4b08b1e4043a29214cc7ad77644c00≥ 407958a0e980b9e1842ab87b5a1040521e1e24e9 and < e2d2115e56c4a02377189bfc3a9a7933552a7b0fversion fc2778c42f99c7de52fc004157b3c3ee4dcc208a≥ 6.4.4 and < 6.5version 6.5	Vulnerable	CVE Program (cve.org) e CISA ADP
Linux	Linux Kernel	≥ 6.4.4 and < 6.12.37≥ 6.13 and < 6.15.3	Vulnerable	NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Local

Attack complexity

Low

Privileges required

Low

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

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	nvd@nist.gov via NIST National Vulnerability Database
7.8	CVSS 3.1	High	—	—	GitHub, Inc. via GitHub Security Advisories

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)

EPSS over time FIRST

Oct 20, 2026 → Oct 27, 2026 · 8 reading(s) · max 0.24%

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.

endpoint telemetry (EDR)

Timeline

What happened to this CVE, newest first.

2026
Affected products added · linux/linux
Oct 21, 2026 · CVE Program (cve.org) e CISA ADP
Record published
Oct 21, 2026
Fix documented
Oct 21, 2026 · NIST National Vulnerability Database
Affected products added · linux/linux kernel
Oct 21, 2026 · NIST National Vulnerability Database
CVSS changed · 7.8
Oct 21, 2026 · NIST National Vulnerability Database
Source status changed · → Modified
Oct 21, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 21, 2026 · Alertas do Telegram
2025
CVE published
Jul 10, 2025 · Linux

Source activity

Repeated readings are counted rather than listed.

2× References added · Oct 21, 2026 – Oct 21, 2026
1× Official description updated · Oct 21, 2026 – Oct 21, 2026

References

6 on the record

git.kernel.org/stable/c/4265682c29c92f52c0da6fad5a79b5801462c8de
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/ac49b7560b4b08b1e4043a29214cc7ad77644c00
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/e2d2115e56c4a02377189bfc3a9a7933552a7b0f
Patch, NIST National Vulnerability Database
git.kernel.org/stable/c/2d9a8022009d2d6ad7aaea249902d88f1fa70144
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2025-38279
GitHub Security Advisories
github.com/advisories/GHSA-f7v2-pww5-gxcf
GitHub Security Advisories

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99215 power: supply: core: prevent unregistering a power supply while a callback runs 2h
Unknown CVE-2026-99216 Drivers: hv: Don't reset VMBus connection state on error/exit paths 2h
Unknown CVE-2026-99214 drm/vc4: hdmi: Move packet RAM enable to PM runtime 2h
Unknown CVE-2026-99213 vsock: treat TCP_CLOSING as once-established 2h
Unknown CVE-2026-99212 net/rds: don't let the rdma_cm destroy an id RDS still owns on route failure 2h
Unknown CVE-2026-99211 netlink: reset skb headers before unicast and multicast filtering 2h

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 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-2025-38279 is "bpf: Do not include stack ptr register in precision backtracking bookkeeping", 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 0.24% 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.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.