CVE-2024-38578 — ecryptfs: Fix buffer size for tag 66 packet
In the Linux kernel, the following vulnerability has been resolved: ecryptfs: Fix buffer size for tag 66 packet The 'TAG 66 Packet Format' description is missing the cipher code and checksum fields that are packed into the message packet. As a result, the buffer allocated for the packet is 3 bytes too small and write_tag_66_packet() will write up to 3 bytes past the end of the buffer. Fix this by increasing the size of the allocation so the whole packet will always fit in the buffer. This fixes the below kasan slab-out-of-bounds bug: BUG: KASAN: slab-out-of-bounds in ecryptfs_generate_key_packet_set+0x7d6/0xde0 Write of size 1 at addr ffff88800afbb2a5 by task touch/181 CPU: 0 PID: 181 Comm: touch Not tainted 6.6.13-gnu #1 4c9534092be820851bb687b82d1f92a426598dc6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.2/GNU Guix 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x4c/0x70 print_report+0xc5/0x610 ? ecryptfs_generate_key_packet_set+0x7d6/0xde0 ? kasan_complete_mode_report_info+0x44/0x210 ? ecryptfs_generate_key_packet_set+0x7d6/0xde0 kasan_report+0xc2/0x110 ? ecryptfs_generate_key_packet_set+0x7d6/0xde0 __asan_store1+0x62/0x80 ecryptfs_generate_key_packet_set+0x7d6/0xde0 ? __pfx_ecryptfs_generate_key_packet_set+0x10/0x10 ? __alloc_pages+0x2e2/0x540 ? __pfx_ovl_open+0x10/0x10 [overlay 30837f11141636a8e1793533a02e6e2e885dad1d] ? dentry_open+0x8f/0xd0 ecryptfs_write_metadata+0x30a/0x550 ? __pfx_ecryptfs_write_metadata+0x10/0x10 ? ecryptfs_get_lower_file+0x6b/0x190 ecryptfs_initialize_file+0x77/0x150 ecryptfs_create+0x1c2/0x2f0 path_openat+0x17cf/0x1ba0 ? __pfx_path_openat+0x10/0x10 do_filp_open+0x15e/0x290 ? __pfx_do_filp_open+0x10/0x10 ? __kasan_check_write+0x18/0x30 ? _raw_spin_lock+0x86/0xf0 ? __pfx__raw_spin_lock+0x10/0x10 ? __kasan_check_write+0x18/0x30 ? alloc_fd+0xf4/0x330 do_sys_openat2+0x122/0x160 ? __pfx_do_sys_openat2+0x10/0x10 __x64_sys_openat+0xef/0x170 ? __pfx___x64_sys_openat+0x10/0x10 do_syscall_64+0x60/0xd0 entry_SYSCALL_64_after_hwframe+0x6e/0xd8 RIP: 0033:0x7f00a703fd67 Code: 25 00 00 41 00 3d 00 00 41 00 74 37 64 8b 04 25 18 00 00 00 85 c0 75 5b 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 85 00 00 00 48 83 c4 68 5d 41 5c c3 0f 1f RSP: 002b:00007ffc088e30b0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffc088e3368 RCX: 00007f00a703fd67 RDX: 0000000000000941 RSI: 00007ffc088e48d7 RDI: 00000000ffffff9c RBP: 00007ffc088e48d7 R08: 0000000000000001 R09: 0000000000000000 R10: 00000000000001b6 R11: 0000000000000246 R12: 0000000000000941 R13: 0000000000000000 R14: 00007ffc088e48d7 R15: 00007f00a7180040 </TASK> Allocated by task 181: kasan_save_stack+0x2f/0x60 kasan_set_track+0x29/0x40 kasan_save_alloc_info+0x25/0x40 __kasan_kmalloc+0xc5/0xd0 __kmalloc+0x66/0x160 ecryptfs_generate_key_packet_set+0x6d2/0xde0 ecryptfs_write_metadata+0x30a/0x550 ecryptfs_initialize_file+0x77/0x150 ecryptfs_create+0x1c2/0x2f0 path_openat+0x17cf/0x1ba0 do_filp_open+0x15e/0x290 do_sys_openat2+0x122/0x160 __x64_sys_openat+0xef/0x170 do_syscall_64+0x60/0xd0 entry_SYSCALL_64_after_hwframe+0x6e/0xd8
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 0.3% (30-day exploitation probability)+3
- 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)
- 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).
- 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 |
≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < 235b85981051cd68fc215fd32a81c6f116bfc4dfversion 2.6.21≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < 85a6a1aff08ec9f5b929d345d066e2830e8818e5≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < f6008487f1eeb8693f8d2a36a89c87d9122ddf74≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < a20f09452e2f58f761d11ad7b96b5c894c91030e≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < 2ed750b7ae1b5dc72896d7dd114c419afd3d1910≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < 0d0f8ba042af16519f1ef7dd10463a33b21b677c≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < 12db25a54ce6bb22b0af28010fff53ef9cb3fe93 and 2 more≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < edbfc42ab080e78c6907d40a42c9d10b69e445c1≥ dddfa461fc8951f9b5f951c13565b6cac678635a and < 1c125b9287e58f364d82174efb167414b92b11f1 |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 2.6.21 and < 4.19.316≥ 6.9 and < 6.9.3≥ 6.7 and < 6.8.12≥ 6.2 and < 6.6.33≥ 5.16 and < 6.1.93≥ 5.11 and < 5.15.161≥ 5.5 and < 5.10.219≥ 4.20 and < 5.4.278 | 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 | 1.8 | 5.9 | nvd@nist.gov via NIST National Vulnerability Database |
| 7.8 | CVSS 3.1 | High | — | — | GitHub, Inc. via GitHub Security Advisories |
| 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: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 14, 2026 → Oct 15, 2026 · 2 reading(s) · max 0.26%
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
- Affected products added · linux/linux
- SSVC assessment updated
- Record published
- Fix documented
- Affected products added · linux/linux kernel
- CVSS changed · 7.8
- Source status changed · → Modified
- Record created in this database
- 2024
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 2× References added · Oct 14, 2026 – Oct 14, 2026
- 1× Official description updated · Oct 14, 2026 – Oct 14, 2026
References
14 on the record
- git.kernel.org/stable/c/2ed750b7ae1b5dc72896d7dd114c419afd3d1910
- git.kernel.org/stable/c/85a6a1aff08ec9f5b929d345d066e2830e8818e5
- git.kernel.org/stable/c/0d0f8ba042af16519f1ef7dd10463a33b21b677c
- git.kernel.org/stable/c/f6008487f1eeb8693f8d2a36a89c87d9122ddf74
- git.kernel.org/stable/c/235b85981051cd68fc215fd32a81c6f116bfc4df
- git.kernel.org/stable/c/edbfc42ab080e78c6907d40a42c9d10b69e445c1
- git.kernel.org/stable/c/a20f09452e2f58f761d11ad7b96b5c894c91030e
- git.kernel.org/stable/c/1c125b9287e58f364d82174efb167414b92b11f1
- git.kernel.org/stable/c/12db25a54ce6bb22b0af28010fff53ef9cb3fe93
- cert-portal.siemens.com/productcert/html/ssa-613116.html
- lists.debian.org/debian-lts-announce/2024/06/msg00020.html
- nvd.nist.gov/vuln/detail/CVE-2024-38578
- github.com/advisories/GHSA-q624-v3v9-vmp4
- cert-portal.siemens.com/productcert/html/ssa-265688.html
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 15h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 15h
- 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
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 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-2024-38578 is "ecryptfs: Fix buffer size for tag 66 packet", 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 0.26% 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.
Sign in or create an account to comment and suggest corrections.