CVE-2021-47458: ocfs2: mount fails with buffer overflow in strlen
Vulnerability summary
CVE-2021-47458 is a high (CVSS 7.8) Out-of-bounds Write vulnerability in linux. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 16.2% of scored vulnerabilities.
Not severe (CVSS 7.1, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 10 · Related 10Timeline
- 22-05-2024PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: ocfs2: mount fails with buffer overflow in strlen Starting with kernel 5.11 built with CONFIG_FORTIFY_SOURCE mouting an ocfs2 filesystem with either o2cb or pcmk cluster stack fails with the trace below. Problem seems to be that strings for cluster stack and cluster name are not guaranteed to be null terminated in the disk representation, while strlcpy assumes that the source string is always null terminated. This causes a read outside of the source string triggering the buffer overflow detection. detected buffer overflow in strlen ------------[ cut here ]------------ kernel BUG at lib/string.c:1149! invalid opcode: 0000 [#1] SMP PTI CPU: 1 PID: 910 Comm: mount.ocfs2 Not tainted 5.14.0-1-amd64 #1 Debian 5.14.6-2 RIP: 0010:fortify_panic+0xf/0x11 ... Call Trace: ocfs2_initialize_super.isra.0.cold+0xc/0x18 [ocfs2] ocfs2_fill_super+0x359/0x19b0 [ocfs2] mount_bdev+0x185/0x1b0 legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 path_mount+0x454/0xa20 __x64_sys_mount+0x103/0x140 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae
CVSS metrics
4 scores · 4 sources · 1 version- CVE.orgCNA7.1HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:HDiffers
- OSV · UbuntuEcosystem advisory · calculated7.1HighCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:HDiffers
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.25%
Chance of exploitation in the next 30 days
Percentile
16%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.25% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, no authentication, user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu88 products
- linuxAll versions (No fix recorded) | < 4.15.0-166.174 | < 5.4.0-92.103
- linux-allwinner-5.19All versions (No fix recorded)
- linux-awsAll versions (No fix recorded) | < 4.15.0-1118.125 | < 5.4.0-1061.64
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < ac011cb3ff7a76b3e0e6e77158ee4ba2f929e1fb | ≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < 4b74ddcc22ee6455946e80a9c4808801f8f8561e | ≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < 232ed9752510de4436468b653d145565669c8498 | ≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < 7623b1035ca2d17bde0f6a086ad6844a34648df1 | ≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < d3a83576378b4c904f711598dde2c5e881c4295c | ≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < 93be0eeea14cf39235e585c8f56df3b3859deaad | ≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < 0e677ea5b7396f715a76b6b0ef441430e4c4b57f | ≥ c74a3bdd9b529d924d1abf986079b783dd105ace, < b15fa9224e6e1239414525d8d556d824701849fc | 3.14
- linux_kernel< 4.4.290 | ≥ 4.5, < 4.9.288 | ≥ 4.10, < 4.14.253 | ≥ 4.15, < 4.19.214 | ≥ 4.20, < 5.4.156 | ≥ 5.5, < 5.10.76 | ≥ 5.11, < 5.14.15 | 5.15:rc1 | 5.15:rc2 | 5.15:rc3 | 5.15:rc4 | 5.15:rc5 | 5.15:rc6
Debian1 product
- linux< 5.14.16-1
3 vendors · 91 products
