CVE-2024-21662 | Argo CD vulnerable to Bypassing of Rate Limit and Brute Force Protection Using Cache Overflow

Exp

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. Prior to versions 2.8.13, 2.9.9, and 2.10.4, an attacker can effectively bypass the rate limit and brute force protections by exploiting the application's weak cache-based mechanism. This loophole in security can be combined with other vulnerabilities to attack the default admin account. This flaw undermines a patch for CVE-2020-8827 intended to protect against brute-force attacks. The application's brute force protection relies on a cache mechanism that tracks login attempts for each user. This cache is limited to a `defaultMaxCacheSize` of 1000 entries. An attacker can overflow this cache by bombarding it with login attempts for different users, thereby pushing out the admin account's failed attempts and effectively resetting the rate limit for that account. This is a severe vulnerability that enables attackers to perform brute force attacks at an accelerated rate, especially targeting the default admin account. Users should upgrade to version 2.8.13, 2.9.9, or 2.10.4 to receive a patch.

Published: 2024-03-18 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2024-21662 is rated High Exploit Risk (64.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.84%). Core evidence: 1 public exploit reference(s) are indexed (Exploit-DB). Mandatory action: Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2024-21662

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2024-21662

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.14% 0.84% +0.70%
2 2025-11-21 0.39% 0.14% -0.26%
3 2025-11-18 0.39%

Full EPSS history (10 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2024-21662

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 5.2 [email protected]

Weakness enumeration for CVE-2024-21662

GitHub Security Advisory for CVE-2024-21662

GHSA-2vgg-9h6w-m454 · Severity: medium · Ecosystem: go — Bypassing Rate Limit and Brute Force Protection Using Cache Overflow

OS Trackers for CVE-2024-21662

vendor priority summary link
redhat medium https://access.redhat.com/security/cve/CVE-2024-21662

Affected software / configurations for CVE-2024-21662

Vendor Product Version Raw CPE
argoproj argo_cd < 2.8.13 cpe:2.3:a:argoproj:argo_cd:*:*:*:*:*:*:*:*
argoproj argo_cd >= 2.9.0, < 2.9.9 cpe:2.3:a:argoproj:argo_cd:*:*:*:*:*:*:*:*
argoproj argo_cd >= 2.10.0, < 2.10.4 cpe:2.3:a:argoproj:argo_cd:*:*:*:*:*:*:*:*

References for CVE-2024-21662

cvelogic Threat Intelligence