Look up another CVE · open CVE-2026-53006 in the interactive tracker
CVE-2026-53006
ipv6: fix possible UAF in icmpv6_rcv()
Published 2026-06-24 (4 months ago) by the Linux kernel CNA. Subsystem net/ipv6. Debian urgency: not yet assigned.
What to do, per Debian release
Debian's own status for CVE-2026-53006 in every release this site tracks, and what each one means in practice. Every status below is the one the Debian Security Team publishes for this CVE. source
| Release | Status | Version | What this means |
|---|---|---|---|
| Debian 12bookworm | fixedDLA-4665-1 · 2026-07-03 · text | 6.1.176-1 | Update the kernel and reboot. DLA-4665-1 shipped the fix on 2026-07-03, in 6.1.176-1. A running kernel keeps the old code until the machine restarts. |
| Debian 13trixie | fixed | 6.12.94-1 | Update the kernel and reboot. Fixed in 6.12.94-1. A running kernel keeps the old code until the machine restarts. |
| Debian 14forky | fixed | 7.0.10-1 | Update the kernel and reboot. Fixed in 7.0.10-1. A running kernel keeps the old code until the machine restarts. |
| Debian unstablesid | fixed | 7.0.10-1 | Update the kernel and reboot. Fixed in 7.0.10-1. A running kernel keeps the old code until the machine restarts. |
The vulnerability
What the bug is
Caching saddr and daddr before pskb_pull() is problematic since skb->head can change. Remove these temporary variables: - We only access &ipv6_hdr(skb)->saddr and &ipv6_hdr(skb)->daddr when net_dbg_ratelimited() is called in the slow path. - Avoid potential future misuse after pskb_pull() call.
Where it lives
The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.
net/ipv6/icmp.c
- What this is
- NETWORKING [IPv4/IPv6]MAINTAINERS section matched on net/ipv6/icmp.c · netdev@vger.kernel.org · Maintained
Check it on the machine
grep -w CONFIG_IPV6 /boot/config-$(uname -r)Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.
Show whether Debian builds this, per release
Debian builds this code. Every release below compiles the affected file into the kernels it ships.
- bookworm, trixie, forky, sidy
- y
- built into the kernel image on every flavour - only a patch removes it
- Build switch
- CONFIG_IPV6
From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages
Signals
- Published
- 2026-06-24 (4 months ago)source
- CVSS
- 9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsource recompute it - Attack vector
- network (AV:N)source
- EPSS
- 0.39%, higher than 32.1% of all CVEssource
- CISA KEV
- not listedthe KEV catalogue
- Debian urgency
- not yet assignedsource
- Subsystem
- net/ipv6
Upstream fixes
The versions the CNA records as introducing and fixing this, and the commit for each. source
| Introduced | Fixed in | Commit |
|---|---|---|
| 4.4 | 5.10.258 | 7bff2c8fe5c3 |
| 4.4 | 5.15.209 | aff0f28f5be8 |
| 4.4 | 6.1.175 | 38bdbc897c0d |
| 4.4 | 6.6.141 | 0069813e6ca9 |
| 4.4 | 6.12.91 | 1e1f0f89ee46 |
| 4.4 | 6.18.33 | 7c66b368c6ff |
| 4.4 | 7.0.10 | 085e31a811ef |
| 4.4 | 7.1 | f996edd7615e |
Debian advisories
| Advisory | Date | Shipped to | Debian |
|---|---|---|---|
| DLA-4671-1 | 2026-07-05 | bullseye 6.1.176-1~deb11u1 | tracker |
| DLA-4665-1 | 2026-07-03 | bookworm 6.1.176-1 | tracker |
| DLA-4664-1 | 2026-07-03 | bullseye 5.10.259-1 | tracker |
Why the CNA scored it this way
Quoted from the kernel CNA's own scoring file, word for word. A highlighted metric carries the most severe value CVSS v3.1 defines for it, which is what pushes the score up. source
- AV:NAttack vector, network
- icmpv6_rcv() is reached by inbound IPv6 ICMPv6 packets through the normal network receive path. A remote IPv6 peer can send crafted ICMPv6 packets to a reachable host without local access.
- AC:LAttack complexity, low
- The attacker can craft the ICMPv6 type, checksum, and fragmentation/non-linear skb layout needed to reach the stale-pointer path after pskb_pull(). There is no attacker-uncontrolled race required.
- PR:NPrivileges required, none
- Inbound ICMPv6 processing occurs before any user authentication or privilege check. No local account or kernel capability is required to send the triggering packets.
- UI:NUser interaction, none
- No victim user action is required. The kernel processes the packets automatically on receive.
- S:UScope, unchanged
- The impact is within the vulnerable kernel/network stack security authority. This is not a guest-to-host escape or other cross-scope boundary bypass.
- C:HConfidentiality impact, high
- The bug is a use-after-free of IPv6 address pointers into skb->head after pskb_pull() can reallocate and free that buffer. Under the required conservative kernel guidance, UAF is treated as high confidentiality impact due potential freed-kernel-memory disclosure.
- I:HIntegrity impact, high
- This is a kernel heap use-after-free in a remote packet-processing path. Under the required conservative kernel guidance, UAF is treated as high integrity impact because heap reuse/spraying can make UAFs exploitable beyond the immediate stale read.
- A:HAvailability impact, high
- A remotely triggerable kernel UAF can produce an oops/panic or repeated fault, especially in debug/KASAN or hardened deployments. Repeated crafted packets can therefore cause high availability impact.