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[AutoPR- Security] Patch gnutls for CVE-2026-5260 [HIGH] #17592

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[AutoPR- Security] Patch gnutls for CVE-2026-5260 [HIGH] #17592

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109 changes: 109 additions & 0 deletions SPECS/gnutls/CVE-2026-5260.patch
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Original file line number Diff line number Diff line change
@@ -0,0 +1,109 @@
From 0c2466de2f0418316021d9bfade9f07536fe998a Mon Sep 17 00:00:00 2001
From: Alexander Sosedkin <asosedkin@redhat.com>
Date: Mon, 30 Mar 2026 17:31:07 +0200
Subject: [PATCH 1/2] lib/auth/rsa: check that ciphertext matches the modulus
size

A client sending extremely short premaster secret as part of an
RSA key exchange could've theoretically triggered a short heap overread
to nowhere when the RSA key was backed with a PKCS#11 token.
With this fix, the internal decryption function will not be called
with an mismatching plaintext length specified, avoiding the overread.

Reported-by: Joshua Rogers of AISLE Research Team <joshua@joshua.hu>
Fixes: #1814
Fixes: CVE-2026-5260
Fixes: GNUTLS-SA-2026-04-29-10
CVSS: 5.9 Medium CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Signed-off-by: Alexander Sosedkin <asosedkin@redhat.com>
---
lib/auth/rsa.c | 5 +++++
lib/auth/rsa_psk.c | 5 +++++
2 files changed, 10 insertions(+)

diff --git a/lib/auth/rsa.c b/lib/auth/rsa.c
index b5ecc09..24c1649 100644
--- a/lib/auth/rsa.c
+++ b/lib/auth/rsa.c
@@ -158,6 +158,7 @@ static int proc_rsa_client_kx(gnutls_session_t session, uint8_t *data,
int ret, dsize;
ssize_t data_size = _data_size;
volatile uint8_t ver_maj, ver_min;
+ unsigned int key_bits;

#ifdef ENABLE_SSL3
if (get_num_version(session) == GNUTLS_SSL3) {
@@ -180,6 +181,10 @@ static int proc_rsa_client_kx(gnutls_session_t session, uint8_t *data,
}
ciphertext.size = dsize;
}
+ gnutls_privkey_get_pk_algorithm(session->internals.selected_key,
+ &key_bits);
+ if (ciphertext.size != (key_bits + 7) / 8)
+ return gnutls_assert_val(GNUTLS_E_DECRYPTION_FAILED);

ver_maj = _gnutls_get_adv_version_major(session);
ver_min = _gnutls_get_adv_version_minor(session);
diff --git a/lib/auth/rsa_psk.c b/lib/auth/rsa_psk.c
index 399fb4d..7a99d87 100644
--- a/lib/auth/rsa_psk.c
+++ b/lib/auth/rsa_psk.c
@@ -257,6 +257,7 @@ static int _gnutls_proc_rsa_psk_client_kx(gnutls_session_t session,
ssize_t data_size = _data_size;
gnutls_psk_server_credentials_t cred;
volatile uint8_t ver_maj, ver_min;
+ unsigned int rsa_key_bits;

cred = (gnutls_psk_server_credentials_t)_gnutls_get_cred(
session, GNUTLS_CRD_PSK);
@@ -313,6 +314,10 @@ static int _gnutls_proc_rsa_psk_client_kx(gnutls_session_t session,
return GNUTLS_E_UNEXPECTED_PACKET_LENGTH;
}
ciphertext.size = dsize;
+ gnutls_privkey_get_pk_algorithm(session->internals.selected_key,
+ &rsa_key_bits);
+ if (ciphertext.size != (rsa_key_bits + 7) / 8)
+ return gnutls_assert_val(GNUTLS_E_DECRYPTION_FAILED);

ver_maj = _gnutls_get_adv_version_major(session);
ver_min = _gnutls_get_adv_version_minor(session);
--
2.45.4


From a8c5bc3b2e6cf7de6c511b2e95f716ddf7935882 Mon Sep 17 00:00:00 2001
From: Alexander Sosedkin <asosedkin@redhat.com>
Date: Mon, 30 Mar 2026 17:46:40 +0200
Subject: [PATCH 2/2] lib/pkcs11_privkey: guard against overreading on short
ciphertexts

This is an alternative fix for the callee side.

Reported-by: Joshua Rogers of AISLE Research Team <joshua@joshua.hu>
Fixes: #1814
Fixes: CVE-2026-5260
Fixes: GNUTLS-SA-2026-04-29-10
CVSS: 5.9 Medium CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Signed-off-by: Alexander Sosedkin <asosedkin@redhat.com>
Signed-off-by: Azure Linux Security Servicing Account <azurelinux-security@microsoft.com>
Upstream-reference: https://gitlab.com/gnutls/gnutls/-/commit/77228f2d1ac207d2f894e5a168fbb47e5378e42f.patch https://gitlab.com/gnutls/gnutls/-/commit/cf6bdc5e4df49e5583d3fb4d2296779785f10683.patch
---
lib/pkcs11_privkey.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/pkcs11_privkey.c b/lib/pkcs11_privkey.c
index 5093a6d..369b034 100644
--- a/lib/pkcs11_privkey.c
+++ b/lib/pkcs11_privkey.c
@@ -826,7 +826,7 @@ int _gnutls_pkcs11_privkey_decrypt_data2(gnutls_pkcs11_privkey_t key,
if (ret != 0)
return gnutls_assert_val(GNUTLS_E_LOCKING_ERROR);

- buffer = gnutls_malloc(siglen);
+ buffer = gnutls_malloc(MAX((size_t)siglen, plaintext_size));
if (!buffer) {
gnutls_assert();
return GNUTLS_E_MEMORY_ERROR;
--
2.45.4

6 changes: 5 additions & 1 deletion SPECS/gnutls/gnutls.spec
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Original file line number Diff line number Diff line change
@@ -1,7 +1,7 @@
Summary: The GnuTLS Transport Layer Security Library
Name: gnutls
Version: 3.8.3
Release: 9%{?dist}
Release: 10%{?dist}
License: GPLv3+ AND LGPLv2.1+
Vendor: Microsoft Corporation
Distribution: Azure Linux
Expand All @@ -21,6 +21,7 @@ Patch8: CVE-2025-6395.patch
Patch9: CVE-2025-13151.patch
Patch10: CVE-2025-9820.patch
Patch11: CVE-2026-33845.patch
Patch12: CVE-2026-5260.patch
BuildRequires: autogen-libopts-devel
BuildRequires: gc-devel
BuildRequires: libtasn1-devel
Expand Down Expand Up @@ -102,6 +103,9 @@ sed -i 's/TESTS += test-ciphers-openssl.sh//' tests/slow/Makefile.am
%{_mandir}/man3/*

%changelog
* Mon Jun 01 2026 Azure Linux Security Servicing Account <azurelinux-security@microsoft.com> - 3.8.3-10
- Patch for CVE-2026-5260

* Thu May 07 2026 Akarsh Chaudhary <v-akarshc@microsoft.com>- 3.8.3-9
- Patch for CVE-2026-33845

Expand Down
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