GNU binutils 2.31.1 libbfd elflink.c File Descriptor null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability classified as problematic has been found in GNU binutils 2.31.1 (Programming Tool Software). Affected is some unknown processing of the file elflink.c of the component libbfd. The manipulation as part of a File Descriptor leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. CVE summarizes:

A NULL pointer dereference was discovered in elf_link_add_object_symbols in elflink.c in the Binary File Descriptor (BFD) library (aka libbfd), as distributed in GNU Binutils 2.31.1. This occurs for a crafted ET_DYN with no program headers. A specially crafted ELF file allows remote attackers to cause a denial of service, as demonstrated by ld.

The bug was discovered 12/31/2018. The weakness was published 01/01/2019 (Website). The advisory is available at This vulnerability is traded as CVE-2018-20651 since 01/01/2019. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at SecurityFocus (BID 106440†).







CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
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VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍



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Class: Null pointer dereference
CWE: CWE-476 / CWE-404

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

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


Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Patch: 54025d5812ff100f5f0654eb7e1ffd50f2e37f5f


12/31/2018 🔍
01/01/2019 +1 days 🔍
01/01/2019 +0 days 🔍
01/01/2019 +0 days 🔍
01/01/2019 +0 days 🔍
01/02/2019 +1 days 🔍
06/22/2023 +1632 days 🔍



Advisory: K38336243
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-20651 (🔍)
SecurityFocus: 106440 - GNU Binutils CVE-2018-20651 Denial of Service Vulnerability


Created: 01/02/2019 10:53 AM
Updated: 06/22/2023 04:28 PM
Changes: 01/02/2019 10:53 AM (62), 04/25/2020 04:54 PM (4), 06/22/2023 04:21 PM (4), 06/22/2023 04:28 PM (1)
Complete: 🔍
Cache ID: 44:1C5:40


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