CVE-2021-47291: ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions
Vulnerability summary
CVE-2021-47291 is a high (CVSS 7.8) Out-of-bounds Read vulnerability in linux. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 16.3% of scored vulnerabilities.
Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 44 · Related 44Timeline
- 21-05-2024PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: ipv6: fix another slab-out-of-bounds in fib6_nh_flush_exceptions While running the self-tests on a KASAN enabled kernel, I observed a slab-out-of-bounds splat very similar to the one reported in commit 821bbf79fe46 ("ipv6: Fix KASAN: slab-out-of-bounds Read in fib6_nh_flush_exceptions"). We additionally need to take care of fib6_metrics initialization failure when the caller provides an nh. The fix is similar, explicitly free the route instead of calling fib6_info_release on a half-initialized object.
CVSS metrics
5 scores · 4 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.1HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:HDiffers
- NVDNIST7.1HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:HDiffers
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, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu83 products
- linux< 5.4.0-88.99
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 5.4.0-1057.60
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < 830251361425c5be044db4d826aaf304ea3d14c6 | ≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < ce8fafb68051fba52546f8bbe8621f7641683680 | ≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < 115784bcccf135c3a3548098153413d76f16aae0 | ≥ f88d8ea67fbdbac7a64bfa6ed9a2ba27bb822f74, < 8fb4792f091e608a0a1d353dfdf07ef55a719db5 | 5.3
- linux_kernel≥ 5.3, < 5.4.136 | ≥ 5.5, < 5.10.54 | ≥ 5.11, < 5.13.6 | 5.14:rc1 | 5.14:rc2
Debian1 product
- linux< 5.14.6-1
3 vendors · 86 products
