CVE-2021-41115
Zulip Regular Expression Denial of Service (ReDoS)
Description
Zulip is an open source team chat server. In affected versions Zulip allows organization administrators on a server to configure "linkifiers" that automatically create links from messages that users send, detected via arbitrary regular expressions. Malicious organization administrators could subject the server to a denial-of-service via regular expression complexity attacks; most simply, by configuring a quadratic-time regular expression in a linkifier, and sending messages that exploited it. A regular expression attempted to parse the user-provided regexes to verify that they were safe from ReDoS -- this was both insufficient, as well as _itself_ subject to ReDoS if the organization administrator entered a sufficiently complex invalid regex. Affected users should [upgrade to the just-released Zulip 4.7](https://zulip.readthedocs.io/en/latest/production/upgrade-or-modify.html#upgrading-to-a-release), or [`main`](https://zulip.readthedocs.io/en/latest/production/upgrade-or-modify.html#upgrading-from-a-git-repository).
INFO
Published Date :
Oct. 7, 2021, 11:15 p.m.
Last Modified :
July 17, 2023, 3:18 p.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
3.6
Exploitability Score :
2.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2021-41115.
| URL | Resource |
|---|---|
| https://github.com/zulip/zulip/commit/e2d303c1bb5f538d17dc3d9134bc8858bdece781 | Patch Third Party Advisory |
| https://github.com/zulip/zulip/security/advisories/GHSA-4h36-mqfq-42jg | Patch Third Party Advisory |
| https://securitylab.github.com/advisories/GHSL-2021-118-zulip-zulip/ | Exploit Third Party Advisory |
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2021-41115 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-41115 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by [email protected]
May. 14, 2024
Action Type Old Value New Value -
Reanalysis by [email protected]
Jul. 17, 2023
Action Type Old Value New Value Removed CWE NIST CWE-400 Removed CWE NIST CWE-697 Added CWE NIST CWE-1333 -
Modified Analysis by [email protected]
Sep. 10, 2022
Action Type Old Value New Value Removed CWE NIST NVD-CWE-Other Added CWE NIST CWE-400 Added CWE NIST CWE-697 -
CVE Modified by [email protected]
May. 12, 2022
Action Type Old Value New Value Added CWE GitHub, Inc. CWE-1333 Removed CWE Reason CWE-400 / Outside of 1003 -
Initial Analysis by [email protected]
Oct. 15, 2021
Action Type Old Value New Value Added CVSS V2 NIST (AV:N/AC:L/Au:S/C:N/I:N/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Changed Reference Type https://github.com/zulip/zulip/commit/e2d303c1bb5f538d17dc3d9134bc8858bdece781 No Types Assigned https://github.com/zulip/zulip/commit/e2d303c1bb5f538d17dc3d9134bc8858bdece781 Patch, Third Party Advisory Changed Reference Type https://github.com/zulip/zulip/security/advisories/GHSA-4h36-mqfq-42jg No Types Assigned https://github.com/zulip/zulip/security/advisories/GHSA-4h36-mqfq-42jg Patch, Third Party Advisory Changed Reference Type https://securitylab.github.com/advisories/GHSL-2021-118-zulip-zulip/ No Types Assigned https://securitylab.github.com/advisories/GHSL-2021-118-zulip-zulip/ Exploit, Third Party Advisory Added CWE NIST NVD-CWE-Other Added CPE Configuration OR *cpe:2.3:a:zulip:zulip:*:*:*:*:*:*:*:* versions up to (excluding) 4.7
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-41115 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2021-41115
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.16 }} 0.04%
score
0.51705
percentile