VDB-136601 · CVE-2019-11477 · BID 108818

Linux Kernel SACK TCP Packet integer overflow

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability has been found in Linux Kernel and classified as critical. This vulnerability affects unknown code of the component SACK Handler. The manipulation as part of TCP Packet leads to integer overflow. This vulnerability is documented as CVE-2019-11477. The attack can be initiated remotely. There is not any exploit available. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability was found in Linux Kernel (Operating System) (the affected version unknown). It has been rated as critical. This issue affects an unknown part of the component SACK Handler. The manipulation as part of a TCP Packet leads to a integer overflow vulnerability. Using CWE to declare the problem leads to CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. Impacted is availability.

The weakness was released 06/17/2019 with Netflix as Linux and FreeBSD Kernel: Multiple TCP-based remote denial of service issues as confirmed posting (oss-sec). The advisory is shared at openwall.com. The identification of this vulnerability is CVE-2019-11477 since 04/23/2019. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available.

The commercial vulnerability scanner Qualys is able to test this issue with plugin 237298 (Red Hat Update for kernel (Sad SACK) (RHSA-2019:1483)).

Applying the patch PATCH_net_1_4.patch is able to eliminate this problem. It is possible to mitigate the problem by applying the configuration setting /proc/sys/net/ipv4/tcp_sack = 0. The best possible mitigation is suggested to be patching the affected component. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 108818†). github.com is providing further details. Entries connected to this vulnerability are available at VDB-136651, VDB-136652, VDB-136655 and VDB-148710. 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: 7.4

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

NVD Base Score: 7.5
NVD Vector: 🔍

CNA Base Score: 7.5
CNA Vector (Canonical Ltd.): 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Integer overflow
CWE: CWE-190 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: PATCH_net_1_4.patch
Config: /proc/sys/net/ipv4/tcp_sack = 0

Timelineinfo

04/23/2019 🔍
06/17/2019 +55 days 🔍
06/17/2019 +0 days 🔍
06/17/2019 +0 days 🔍
06/18/2019 +1 days 🔍
10/06/2023 +1571 days 🔍

Sourcesinfo

Vendor: kernel.org

Advisory: Linux and FreeBSD Kernel: Multiple TCP-based remote denial of service issues
Organization: Netflix
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2019-11477 (🔍)
GCVE (CVE): GCVE-0-2019-11477
GCVE (VulDB): GCVE-100-136601
SecurityFocus: 108818 - Linux Kernel CVE-2019-11479 Denial of Service Vulnerability

Misc.: 🔍
See also: 🔍

Entryinfo

Created: 06/18/2019 10:44
Updated: 10/06/2023 08:12
Changes: 06/18/2019 10:44 (68), 06/25/2020 10:19 (4), 10/06/2023 08:11 (5), 10/06/2023 08:12 (11)
Complete: 🔍
Cache ID: 216::103

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

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