Linux Kernel up to 7.2-rc4 GTP drivers/net/gtp.c gtp1u_send_echo_resp return value

CVSS Meta Temp Score
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CTI Interest Score
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7.2$0-$5k1.81

Summaryinfo

A vulnerability identified as critical has been detected in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. The impacted element is the function gtp1u_send_echo_resp of the file drivers/net/gtp.c of the component GTP. The manipulation leads to return value. This vulnerability is traded as CVE-2026-64577. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.6.147/6.12.100/6.18.41/7.1.5/7.2-rc4. This issue affects the function gtp1u_send_echo_resp of the file drivers/net/gtp.c of the component GTP. The manipulation with an unknown input leads to a return value vulnerability. Using CWE to declare the problem leads to CWE-252. The product does not check the return value from a method or function, which can prevent it from detecting unexpected states and conditions. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: gtp: check skb_pull_data() return in gtp1u_send_echo_resp() gtp1u_send_echo_resp() ignores skb_pull_data()'s return value. Its caller gtp1u_udp_encap_recv() only guarantees 16 bytes (udphdr + gtp1_header), but the pull requests 20 (gtp1_header_long + udphdr). For a 16-19 byte echo request the pull fails and returns NULL without advancing skb->data; execution continues, and the following skb_push() plus the IP header pushed by iptunnel_xmit() move skb->data below skb->head, tripping skb_under_panic(). Fix it by dropping the packet when skb_pull_data() fails. skbuff: skb_under_panic: ... kernel BUG at net/core/skbuff.c:214! Call Trace: skb_push (net/core/skbuff.c:2648) iptunnel_xmit (net/ipv4/ip_tunnel_core.c:82) gtp_encap_recv (drivers/net/gtp.c:701 drivers/net/gtp.c:808 drivers/net/gtp.c:920) udp_queue_rcv_one_skb (net/ipv4/udp.c:2388) ... Kernel panic - not syncing: Fatal exception in interrupt

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2026-64577 since 07/19/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/05/2026).

Upgrading to version 6.6.148, 6.12.101, 6.18.42, 7.1.6 or 7.2-rc5 eliminates this vulnerability. Applying the patch b3c733eaae7f362601c28ac1533d47a961cd3e1c/4fc7923871d176ce0e5fecf4a9b7bb915af790ed/961e9b1e33445f8e42859ecc020c9f60d8b69a8b/cf45d748e437b8dd2dd987f27ee79c8c86f95c88/cd170f051dba9ac146fabcd1b91726487c0cb9fa is able to eliminate this problem.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-53271). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.2

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Return value
CWE: CWE-252 / CWE-253
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.6.148/6.12.101/6.18.42/7.1.6/7.2-rc5
Patch: b3c733eaae7f362601c28ac1533d47a961cd3e1c/4fc7923871d176ce0e5fecf4a9b7bb915af790ed/961e9b1e33445f8e42859ecc020c9f60d8b69a8b/cf45d748e437b8dd2dd987f27ee79c8c86f95c88/cd170f051dba9ac146fabcd1b91726487c0cb9fa

Timelineinfo

07/19/2026 CVE reserved
08/05/2026 +17 days Advisory disclosed
08/05/2026 +0 days VulDB entry created
08/05/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-64577 (🔒)
GCVE (CVE): GCVE-0-2026-64577
GCVE (VulDB): GCVE-100-386129
EUVD: 🔒

Entryinfo

Created: 08/05/2026 10:24
Updated: 08/05/2026 11:17
Changes: 08/05/2026 10:24 (60), 08/05/2026 11:17 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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