CVE-2026-58314

Two SSRF findings in Gitea 1.26.2

Two SSRF findings in Gitea 1.26.2

| --- | --- | | Versions tested | gitea/gitea:1.26.2 (digest sha256:7d13848af12645600a5f9d93ee2560daa9c6fa6b5b859b7bff3a5e1c0b661031); gitea/gitea:latest resolves to the same digest at time of writing | | Source review | git checkout v1.26.2 (commit 2c749ce) | | Reproduction | bash run_poc.sh (single shot: brings up containers, runs three PoCs, prints captured evidence, tears down on exit) | | Files touched by the fixes | modules/hostmatcher/hostmatcher.go, modules/auth/openid/openid.go |

Summary

Gitea guards outbound HTTP from webhooks and repo migration with net.Dialer.Control, the correct hook point. The IP classifier behind it misses ten address families, of which CGNAT (100.64.0.0/10) is the practically important one because it is plain IPv4 and is used today by Tailscale, AWS VPC secondary CIDRs, and several Kubernetes pod-CIDR conventions. Any logged-in user can create a webhook pointing at an internal CGNAT host. The full HTTP response from that host (status, headers, body up to 1 MB) is stored in the webhook delivery log and rendered to the webhook owner on the hook detail page. The same gap applies to repo migration.

Separately, the OpenID sign-in form at /user/login/openid fetches the user-supplied provider URL server-side via openid-go, which uses http.DefaultClient. No hostmatcher, no IP filter, no CSRF, no authentication. When OpenID sign-in is enabled, anyone on the internet can drive Gitea into making arbitrary GET requests against internal IPs.

Both reproduce on gitea/gitea:1.26.2 (current stable) in default configuration. The bundled run_poc.sh reproduces all three primitives end-to-end in about one minute and tears the lab down at exit.

Finding 1: hostmatcher classifier passes CGNAT and IPv6 transition prefixes

The bug

modules/hostmatcher/hostmatcher.go:107-119, the external builtin:

case MatchBuiltinExternal:
    if ip.IsGlobalUnicast() && !ip.IsPrivate() {
        return true
    }

IsGlobalUnicast() && !IsPrivate() was written for stack bookkeeping, not as a security boundary. It catches RFC 1918, RFC 4193 ULA, link-local, loopback, and the IPv4-mapped ::ffff:0:0/96 prefix (because IsPrivate un-embeds that range via net.IP.To4()). Every other IPv6 transition prefix returns nil from To4(), so the embedded IPv4 is invisible to the classifier.

Address families that pass the guard, verified live on 1.26.2:

| Family | Example | Why missed | | --- | --- | --- | | CGNAT, RFC 6598 | 100.64.0.1 | IsPrivate() checks 10/8, 172.16/12, 192.168/16 only | | NAT64 well-known, RFC 6052 | 64:ff9b::7f00:1 | To4() un-embeds only ::ffff:0:0/96 | | NAT64 local-use, RFC 8215 | 64:ff9b:1::1 | same | | 6to4, RFC 3056 | 2002:7f00:1:: | same | | Teredo, RFC 4380 | 2001::abcd | same | | IPv4-compatible | ::169.254.169.254 | same | | SIIT, RFC 6145 | ::ffff:0:7f00:1 | same | | Documentation | 2001:db8::1 | same | | Benchmarking, RFC 2544 | 198.18.0.1 | not in any private check | | TEST-NET, RFC 5737 | 192.0.2.1 | same |

CGNAT is the one that needs no IPv6 infrastructure. The 100.64.0.0/10 block overlaps with Tailscale (100.x), AWS VPC secondary CIDRs, and several Kubernetes pod-CIDR conventions. Any Gitea instance that shares a network with services on a CGNAT address is exploitable in default config.

NAT64, 6to4, Teredo, and SIIT need the matching gateway on the network to actually carry the packet. The guard still passes the address, so the bug is real at the guard layer; impact depends on whether the deployment has the corresponding transition mechanism. Lab confirmed: the guard passes, the connection then fails with network is unreachable on a stock Linux box.

The wrapping net.Dialer.Control callback is structurally correct (fires per redirect hop, post-DNS, pre-connect). The classifier is the only broken part.

Reachable sinks

Webhook delivery, services/webhook/deliver.go:

// :321-328
webhookHTTPClient =…

Two SSRF findings in Gitea 1.26.2

Two SSRF findings in Gitea 1.26.2

| --- | --- | | Versions tested | gitea/gitea:1.26.2 (digest sha256:7d13848af12645600a5f9d93ee2560daa9c6fa6b5b859b7bff3a5e1c0b661031); gitea/gitea:latest resolves to the same digest at time of writing | | Source review | git checkout v1.26.2 (commit 2c749ce) | | Reproduction | bash run_poc.sh (single shot: brings up containers, runs three PoCs, prints captured evidence, tears down on exit) | | Files touched by the fixes | modules/hostmatcher/hostmatcher.go, modules/auth/openid/openid.go |

Summary

Gitea guards outbound HTTP from webhooks and repo migration with net.Dialer.Control, the correct hook point. The IP classifier behind it misses ten address families, of which CGNAT (100.64.0.0/10) is the practically important one because it is plain IPv4 and is used today by Tailscale, AWS VPC secondary CIDRs, and several Kubernetes pod-CIDR conventions. Any logged-in user can create a webhook pointing at an internal CGNAT host. The full HTTP response from that host (status, headers, body up to 1 MB) is stored in the webhook delivery log and rendered to the webhook owner on the hook detail page. The same gap applies to repo migration.

Separately, the OpenID sign-in form at /user/login/openid fetches the user-supplied provider URL server-side via openid-go, which uses http.DefaultClient. No hostmatcher, no IP filter, no CSRF, no authentication. When OpenID sign-in is enabled, anyone on the internet can drive Gitea into making arbitrary GET requests against internal IPs.

Both reproduce on gitea/gitea:1.26.2 (current stable) in default configuration. The bundled run_poc.sh reproduces all three primitives end-to-end in about one minute and tears the lab down at exit.

Finding 1: hostmatcher classifier passes CGNAT and IPv6 transition prefixes

The bug

modules/hostmatcher/hostmatcher.go:107-119, the external builtin:

case MatchBuiltinExternal:
    if ip.IsGlobalUnicast() && !ip.IsPrivate() {
        return true
    }

IsGlobalUnicast() && !IsPrivate() was written for stack bookkeeping, not as a security boundary. It catches RFC 1918, RFC 4193 ULA, link-local, loopback, and the IPv4-mapped ::ffff:0:0/96 prefix (because IsPrivate un-embeds that range via net.IP.To4()). Every other IPv6 transition prefix returns nil from To4(), so the embedded IPv4 is invisible to the classifier.

Address families that pass the guard, verified live on 1.26.2:

| Family | Example | Why missed | | --- | --- | --- | | CGNAT, RFC 6598 | 100.64.0.1 | IsPrivate() checks 10/8, 172.16/12, 192.168/16 only | | NAT64 well-known, RFC 6052 | 64:ff9b::7f00:1 | To4() un-embeds only ::ffff:0:0/96 | | NAT64 local-use, RFC 8215 | 64:ff9b:1::1 | same | | 6to4, RFC 3056 | 2002:7f00:1:: | same | | Teredo, RFC 4380 | 2001::abcd | same | | IPv4-compatible | ::169.254.169.254 | same | | SIIT, RFC 6145 | ::ffff:0:7f00:1 | same | | Documentation | 2001:db8::1 | same | | Benchmarking, RFC 2544 | 198.18.0.1 | not in any private check | | TEST-NET, RFC 5737 | 192.0.2.1 | same |

CGNAT is the one that needs no IPv6 infrastructure. The 100.64.0.0/10 block overlaps with Tailscale (100.x), AWS VPC secondary CIDRs, and several Kubernetes pod-CIDR conventions. Any Gitea instance that shares a network with services on a CGNAT address is exploitable in default config.

NAT64, 6to4, Teredo, and SIIT need the matching gateway on the network to actually carry the packet. The guard still passes the address, so the bug is real at the guard layer; impact depends on whether the deployment has the corresponding transition mechanism. Lab confirmed: the guard passes, the connection then fails with network is unreachable on a stock Linux box.

The wrapping net.Dialer.Control callback is structurally correct (fires per redirect hop, post-DNS, pre-connect). The classifier is the only broken part.

Reachable sinks

Webhook delivery, services/webhook/deliver.go:

// :321-328
webhookHTTPClient =…

Gitea: Two SSRF findings in gitea.dev

This update for govulncheck-vulndb fixes the following issues:

• Update to version 0.0.20260723T184607 2026-07-23T18:46:07Z (jsc#PED-11136).

Go CVE Numbering Authority IDs added or updated with aliases:

• GO-2026-4730 CVE-2026-33022 GHSA-cv4x-93xx-wgfj
• GO-2026-4761 CVE-2026-33211 GHSA-j5q5-j9gm-2w5c
• GO-2026-5102 CVE-2026-45021 GHSA-3vcp-chfh-f6r2
• GO-2026-5272 CVE-2026-40938 GHSA-94jr-7pqp-xhcq
• GO-2026-5486 CVE-2026-40924 GHSA-m2cx-gpqf-qf74
• GO-2026-5542 CVE-2026-40090 GHSA-pj97-4p9w-gx3q
• GO-2026-5630 CVE-2026-25542 GHSA-rmx9-2pp3-xhcr
• GO-2026-5643 CVE-2026-40923 GHSA-rx35-6rhx-7858
• GO-2026-5675 CVE-2026-41492 GHSA-vvf7-6rmr-m29q
• GO-2026-5711 CVE-2026-40161 GHSA-wjxp-xrpv-xpff
• GO-2026-5746 CVE-2026-41567 GHSA-x86f-5xw2-fm2r
• GO-2026-5749 CVE-2026-41328 GHSA-x92x-px7w-4gx4
• GO-2026-5837 CVE-2026-44840 GHSA-q2m9-6jp9-c6mc
• GO-2026-5929 CVE-2026-44342 GHSA-26v7-h57m-gh9m
• GO-2026-5930 CVE-2026-33655 GHSA-6qcr-qxgr-m7fv
• GO-2026-5933 GHSA-3g4q-2f67-2gvh
• GO-2026-5934 GHSA-59qp-cfj3-rp64
• GO-2026-5935 GHSA-7856-g3gv-9wq8
• GO-2026-5936 CVE-2026-53552 GHSA-26rh-24rg-j3vv
• GO-2026-5937 CVE-2026-53508 GHSA-2jcc-mxv7-p3f9
• GO-2026-5938 CVE-2026-53553 GHSA-4g5x-hcwm-82jw
• GO-2026-5939 CVE-2026-10517 GHSA-698x-9w2p-7vvp
• GO-2026-5940 CVE-2026-53572 GHSA-6w3m-4hhp-775q
• GO-2026-5941 CVE-2026-53487 GHSA-gvhc-wv3v-7pf8
• GO-2026-5942 CVE-2026-46600
• GO-2026-5944 CVE-2026-50197 GHSA-659f-rgp5-w4wf
• GO-2026-5945 CVE-2026-6815 GHSA-rmxx-v9rj-vpvg
• GO-2026-5946 CVE-2026-52831 GHSA-v5px-423j-pf7p
• GO-2026-5947 CVE-2026-53649 GHSA-xqhv-chqm-fhcc
• GO-2026-5948 CVE-2026-50554 GHSA-588f-fvcv-xhvf
• GO-2026-5949 CVE-2026-50553 GHSA-rqrh-8wpv-x7hh
• GO-2026-5950 CVE-2026-53602 GHSA-339v-266x-79xr
• GO-2026-5951 CVE-2026-10219 GHSA-6jm8-4fhr-5w64
• GO-2026-5952 CVE-2026-49834 GHSA-9vcr-p3rj-q5q6
• GO-2026-5953 CVE-2026-9094 GHSA-c9w5-qp6m-m395
• GO-2026-5956 CVE-2026-55252 GHSA-h5g6-xmh4-hc37
• GO-2026-5957 CVE-2026-54158 GHSA-5xfx-xj4h-5p7r
• GO-2026-5958 CVE-2026-54068 GHSA-gcm7-57gf-953c
• GO-2026-5959 CVE-2026-54072 GHSA-h29v-hj44-q8cv
• GO-2026-5961 CVE-2026-54069 GHSA-hvr9-72v2-fff3
• GO-2026-5962 CVE-2026-54088 GHSA-m93h-4hw7-5qcm
• GO-2026-5963 CVE-2026-54067 GHSA-mvjr-vv3c-w4qv
• GO-2026-5964 CVE-2026-54066 GHSA-p4m3-mgmm-c664
• GO-2026-5965 CVE-2026-54070 GHSA-w7cg-whh7-xp28
• GO-2026-5966 CVE-2026-54089 GHSA-xqp3-jq6g-x3qm
• GO-2026-5967 CVE-2026-50551 GHSA-56mp-4f3v-fgj2
• GO-2026-5968 CVE-2026-54174 GHSA-fpg8-7664-jc5q
• GO-2026-5969 GHSA-g936-7jqj-mwv8
• GO-2026-5970 CVE-2026-56852
• GO-2026-5973 CVE-2026-54250 GHSA-jxr7-mqhw-9p98
• GO-2026-5974 CVE-2026-44300 GHSA-wmj8-9953-vff5
• GO-2026-5975 CVE-2026-50018 GHSA-42j2-w334-qxw7
• GO-2026-5976 CVE-2026-50141 GHSA-g7mm-9vx7-jm7h
• GO-2026-5977 CVE-2026-50013 GHSA-qrh4-p6v4-mrfg
• GO-2026-5978 CVE-2026-50125 GHSA-qw5r-ppcg-f8rj
• GO-2026-5979 CVE-2026-50006 GHSA-xrcf-6jh3-ggvx
• GO-2026-5980 CVE-2026-50158 GHSA-2c7f-fxww-6w6c
• GO-2026-5981 GHSA-mqxv-9rm6-w8qc
• GO-2026-5982 GHSA-pqg7-v6wh-3pfp
• GO-2026-5984 CVE-2026-53604 GHSA-2p2f-px33-4vv5
• GO-2026-5985 GHSA-7rx3-5wx3-5v76
• GO-2026-5986 CVE-2026-61699 GHSA-cm26-5974-52h8
• GO-2026-5987 CVE-2026-55513 GHSA-g4x6-jcvr-9m3g
• GO-2026-5988 CVE-2026-54628 GHSA-hwrq-8wxh-q4xv
• GO-2026-5989 CVE-2026-55512 GHSA-m3cx-mwpg-32jg
• GO-2026-5990 CVE-2026-54629 GHSA-mf78-3rpf-r784
• GO-2026-5991 CVE-2026-53603 GHSA-q4vm-pq3q-8wgq
• GO-2026-5992 CVE-2026-61549 GHSA-qf34-295c-26v8
• GO-2026-5996 CVE-2026-54450 GHSA-pph6-vfjv-vpjw
• GO-2026-5997 CVE-2026-54452 GHSA-xgch-x3mx-cm3c
• GO-2026-5998 CVE-2026-54495 GHSA-398h-7f66-3h4p
• GO-2026-5999 CVE-2026-10814 GHSA-jh6h-v6mp-h22v
• GO-2026-6002 CVE-2026-58196 GHSA-pr64-jmmf-jp54
• GO-2026-6003 CVE-2026-53714 GHSA-22xc-xg2r-9j7v
• GO-2026-6004 CVE-2026-52833 GHSA-3v79-m2cg-89ww
• GO-2026-6005 CVE-2026-53715 GHSA-8fv2-88gg-hm7q
• GO-2026-6006 CVE-2026-53716 GHSA-cxpq-8v7q-cg56 *…