CVE-2026-43500: Linux kernel · rxrpc: Also unshare DATA/RESPONSE packets when paged frags are present
Affects Linux kernelSource GCVE Database
Public exploit available (Metasploit, Exploit-DB) · 94% EPSS · CVSS 7.8 High · fixed in 5.4.0-1160.170~18.04.1 : patch Linux kernel as a priority.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 94.1% chance of exploitation in 30 days – higher than 99% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 5.4.0-1160.170~18.04.1, 5.4.0-1164.170~18.04.1, 5.4.0-1163.172~18.04.1 +99
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 11 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
1 Metasploit module · 2 Exploit-DB entries, the first 16 days after disclosure
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE published
on cve.org
, t = 0
First Exploit-DB entry (opens in a new tab)
Linux Kernel - Local Privilege Escalation +1 more
, 16 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux@7.0.0-22.22?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws@7.0.0-1006.6?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure@7.0.0-1007.7?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde@7.0.0-1008.8?arch=source&distro=resoluteOther threats | Affected
| Fixed in– |
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp@7.0.0-1005.5?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-ibmpkg:deb/ubuntu/linux-ibm@7.0.0-1007.7?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Also unshare DATA/RESPONSE packets when paged frags are present The DATA-packet handler in rxrpc_input_call_event() and the RESPONSE handler in rxrpc_verify_response() copy the skb to a linear one before calling into the security ops only when skb_cloned() is true. An skb that is not cloned but still carries externally-owned paged fragments (e.g. SKBFL_SHARED_FRAG set by splice() into a UDP socket via __ip_append_data, or a chained skb_has_frag_list()) falls through to the in-place decryption path, which binds the frag pages directly into the AEAD/skcipher SGL via skb_to_sgvec(). Extend the gate to also unshare when skb_has_frag_list() or skb_has_shared_frag() is true. This catches the splice-loopback vector and other externally-shared frag sources while preserving the zero-copy fast path for skbs whose frags are kernel-private (e.g. NIC page_pool RX, GRO). The OOM/trace handling already in place is reused.
References
- ubuntu.com/security/CVE-2026-43500 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-43500 (opens in a new tab)
- openwall.com/lists/oss-security/2026/05/08/8 (opens in a new tab)
- openwall.com/lists/oss-security/2026/05/07/8 (opens in a new tab)
- lore.kernel.org/all/afKV2zGR6rrelPC7@v4bel/ (opens in a new tab)
- ubuntu.com/blog/dirty-frag-linux-vulnerability-fixes-available (opens in a new tab)
- github.com/V4bel/dirtyfrag (opens in a new tab)
- ubuntu.com/security/notices/USN-8370-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8371-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8373-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8374-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8388-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8389-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8391-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8392-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8393-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8426-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8426-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8440-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8388-2 (opens in a new tab)
- wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2403.json (opens in a new tab)
- wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-2403 (opens in a new tab)
- lore.kernel.org/linux-cve-announce/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071915-CVE-2026-53367-b8b1@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071918-CVE-2026-53368-9e8b@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071918-CVE-2026-53369-8633@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071918-CVE-2026-53370-9b22@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071918-CVE-2026-53371-d566@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071919-CVE-2026-53372-07f3@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071944-CVE-2026-53373-3856@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071946-CVE-2026-53374-a981@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071946-CVE-2026-53375-58f4@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071946-CVE-2026-53376-281b@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071947-CVE-2026-53377-a415@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071947-CVE-2026-53378-d41e@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071947-CVE-2026-53379-316d@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071947-CVE-2026-53380-12df@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071931-CVE-2026-53381-73c3@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071933-CVE-2026-53382-a456@gregkh/ (opens in a new tab)
- lore.kernel.org/linux-cve-announce/2026071934-CVE-2026-53383-f003@gregkh/ (opens in a new tab)