CVE-2021-34556In the Linux kernel through 5.13.7, an unprivileged BPF program can obtain sensitive information from kernel memory via a Speculative Store Bypass side-channel attack because the protection mechanism…
Updated under an hour ago ()
Does this affect you?
It affects linux_kernel and 2 other products. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
In the Linux kernel through 5.13.7, an unprivileged BPF program can obtain sensitive information from kernel memory via a Speculative Store Bypass side-channel attack because the protection mechanism neglects the possibility of uninitialized memory locations on the BPF stack.
- CVSS
- 5.5 MEDIUM (v3.1, NVD)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
- Weakness (CWE)
- Not given
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- mitre
- NVD analysis
- Modified
- Record last updated
- Oct 8, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
linux linux_kernel linux:linux_kernel | through 5.13.7 | NVD |
fedoraproject fedora fedoraproject:fedora | 33; 34 | NVD |
debian debian_linux debian:debian_linux | 9.0 | NVD |
References
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/patch/?id=f5e81d1117501546b7be050c5fbafa6efd2c722cx-refsource-misc
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/patch/?id=2039f26f3aca5b0e419b98f65dd36481337b86eex-refsource-misc
- http://www.openwall.com/lists/oss-security/2021/08/01/3x-refsource-misc
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/6JKK6XNRZX5BT5QVYOKGVJ2BHFZAP5EX/vendor-advisory, x-refsource-fedora
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/565ZS55ZFEN62WVRRORT7R63RXW5F4T4/vendor-advisory, x-refsource-fedora
- https://lists.debian.org/debian-lts-announce/2021/10/msg00010.htmlmailing-list, x-refsource-mlist
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.