HAProxy up to 2.1.3 HPACK Decoder hpack-tbl.c hpack_dht_insert Request out-of-bounds write

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.
CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.4$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in HAProxy up to 2.1.3. This issue affects the function hpack_dht_insert of the file hpack-tbl.c of the component HPACK Decoder. The manipulation as part of Request results in out-of-bounds write. This vulnerability is identified as CVE-2020-11100. The attack can be executed remotely. Additionally, an exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in HAProxy up to 2.1.3 (Firewall Software). Affected is the function hpack_dht_insert of the file hpack-tbl.c of the component HPACK Decoder. The manipulation as part of a Request leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

In hpack_dht_insert in hpack-tbl.c in the HPACK decoder in HAProxy 1.8 through 2.x before 2.1.4, a remote attacker can write arbitrary bytes around a certain location on the heap via a crafted HTTP/2 request, possibly causing remote code execution.

The weakness was released 04/02/2020 as Bug 1819111 as not defined bug report (Bugzilla). The advisory is available at bugzilla.redhat.com. This vulnerability is traded as CVE-2020-11100 since 03/30/2020. It is possible to launch the attack remotely. The successful exploitation needs a authentication. Technical details and a public exploit are known.

The exploit is shared for download at packetstormsecurity.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 236649 (Alibaba Cloud Linux 3 : 0043: haproxy (ALINUX3-SA-2022:0043)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 2.1.4 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (236649). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.2

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
💳💳💳💳💳💳
💳💳💳💳💳💳
💳💳💳💳💳💳
VectorComplexityAuthenticationConfidentialityIntegrityAvailability
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock
UnlockUnlockUnlockUnlockUnlockUnlock

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

NVD Base Score: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-DayUnlockUnlockUnlockUnlock
TodayUnlockUnlockUnlockUnlock

Nessus ID: 236649
Nessus Name: Alibaba Cloud Linux 3 : 0043: haproxy (ALINUX3-SA-2022:0043)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: HAProxy 2.1.4
Patch: 5dfc5d5cd0d2128d77253ead3acf03a421ab5b88

Timelineinfo

03/30/2020 🔍
04/02/2020 +3 days 🔍
04/03/2020 +1 days 🔍
05/18/2025 +1871 days 🔍

Sourcesinfo

Advisory: Bug 1819111
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2020-11100 (🔍)
GCVE (CVE): GCVE-0-2020-11100
GCVE (VulDB): GCVE-100-152706
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 04/03/2020 10:07
Updated: 05/18/2025 21:05
Changes: 04/03/2020 10:07 (43), 04/03/2020 10:12 (18), 10/07/2020 10:36 (1), 05/13/2024 12:00 (19), 06/13/2024 11:58 (9), 05/18/2025 21:05 (4)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Discussion

No comments yet. Languages: en.

Please log in to comment.

◂ PreviousOverviewNext ▸

Want to know what is going to be exploited?

We predict KEV entries!