Answer in brief
CVE-2026-63829 records a High severity (CVSS 8.8) vulnerability in net: ip_gre: require CAP_NET_ADMIN in the device netns for changelink. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.8. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=b57708add31494175be741ed3fd24023b50c3423 <19275943d8fe903eb7b9aa53e380e41efd042ada || >=b57708add31494175be741ed3fd24023b50c3423 <866b0f5ae599490bd496fd84581c68ac8b94e6af || >=b57708add31494175be741ed3fd24023b50c3423 <92b766fc55156e0da2ecd0c2302c971118f8a229 || >=b57708add31494175be741ed3fd24023b50c3423 <e54c05ed3d9c28733fb9e5837219aca3691defa3 || >=b57708add31494175be741ed3fd24023b50c3423 <9831bc9ecb402957810c2045c663fbfe9b09e296 || >=b57708add31494175be741ed3fd24023b50c3423 <1697957eb0971d420dde42862b88eb43506a1105 || >=b57708add31494175be741ed3fd24023b50c3423 <47b5d3d506609b08b2e1f7c14f0b681a1953d572 || >=b57708add31494175be741ed3fd24023b50c3423 <8165f7ff57d9667d2bb477ef6af83ede7fed4ad7 | 19275943d8fe903eb7b9aa53e380e41efd042ada, 866b0f5ae599490bd496fd84581c68ac8b94e6af, 92b766fc55156e0da2ecd0c2302c971118f8a229, e54c05ed3d9c28733fb9e5837219aca3691defa3, 9831bc9ecb402957810c2045c663fbfe9b09e296, 1697957eb0971d420dde42862b88eb43506a1105, 47b5d3d506609b08b2e1f7c14f0b681a1953d572, 8165f7ff57d9667d2bb477ef6af83ede7fed4ad7 |
| Linux/Linuxgeneric | 3.16 | Not reported |
Published upstream
Jul 19, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 5, 2026
In the Linux kernel, the following vulnerability has been resolved: net: ip_gre: require CAP_NET_ADMIN in the device netns for changelink A tunnel changelink() operates on at most two netns, dev_net(dev) and the tunnel link netns t->net. They differ once the device is created in or moved to a netns other than the one the request runs in. The rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a caller privileged there but not in t->net can rewrite a tunnel that lives in t->net. Add rtnl_dev_link_net_capable() next to rtnl_get_net_ns_capable() in net/core/rtnetlink.c. It requires CAP_NET_ADMIN in the link netns and is skipped when the link netns is dev_net(dev), where the rtnl path already checked it. The other patches in this series use the same helper. Gate ipgre_changelink() and erspan_changelink() with it, at the top of the op before any attribute is parsed, because the parsers update live tunnel fields first. ipgre_netlink_parms() sets t->collect_md before ip_tunnel_changelink() runs. Commit 8b484efd5cb4 ("ip6: vti: Use ip6_tnl.net in vti6_siocdevprivate().") added the same check on the ioctl path. This adds it on RTM_NEWLINK.
Quoted source text, attributed separately from HOL analysis.