How severe is CVE-2021-3749?

CVE-2021-3749 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-3749 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3749?

CVE-2021-3749 primarily affects Axios. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-3749?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-3749 published?

CVE-2021-3749 was published on 2021-08-31 and last updated on 2026-06-17.

CVE-2021-3749

CVE-2021-3749 is a high-severity vulnerability in Axios with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-1333.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 7.8
EPSS exploit prediction: 9% (94th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Axios
Published: 2021-08-31
Last modified: 2026-06-17

Description

axios is vulnerable to Inefficient Regular Expression Complexity

Frequently asked questions

What is CVE-2021-3749?: axios is vulnerable to Inefficient Regular Expression Complexity
How severe is CVE-2021-3749?: CVE-2021-3749 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-3749 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3749?: CVE-2021-3749 primarily affects Axios. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-3749?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-3749 published?: CVE-2021-3749 was published on 2021-08-31 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:a:axios:axios:*:*:*:*:*:node.js:*:*
cpe:2.3:a:siemens:sinec_ins:*:*:*:*:*:*:*:*
cpe:2.3:a:siemens:sinec_ins:1.0:-:*:*:*:*:*:*
cpe:2.3:a:siemens:sinec_ins:1.0:sp1:*:*:*:*:*:*
cpe:2.3:a:oracle:goldengate:*:*:*:*:*:*:*:*

More vulnerabilities in Axios

CVE-2025-62718 — Critical (CVSS 9.9): Axios is a promise based HTTP client for the browser and Node.js. Prior to 1.15.0 and 0.31.0, Axios does not correctly…
CVE-2026-44494 — High (CVSS 8.7): Axios is a promise based HTTP client for the browser and Node.js. From 1.0.0 to before 1.16.0, the Axios library is…
CVE-2026-44492 — High (CVSS 8.6): Axios is a promise based HTTP client for the browser and Node.js. Prior to 0.32.0 and 1.16.0, Axios does not normalise…
CVE-2026-44496 — High (CVSS 7.5): Axios is a promise based HTTP client for the browser and Node.js. Axios versions before 0.32.0 on the 0.x line and…
CVE-2026-44488 — High (CVSS 7.5): Axios is a promise based HTTP client for the browser and Node.js. Axios versions 1.7.0 through 1.15.x did not enforce…
CVE-2026-44487 — High (CVSS 7.5): Axios is a promise based HTTP client for the browser and Node.js. Prior to 0.32.0 and 1.16.0, Axios’s Node.js HTTP…

All CVEs affecting Axios →

Other CWE-1333 vulnerabilities

CVE-2026-35458 — Critical (CVSS 9.8): Gotenberg is an API for converting document formats. In 8.29.1 and earlier, Gotenberg uses dlclark/regexp2 to compile…
CVE-2023-29486 — Critical (CVSS 9.8): An issue was discovered in Heimdal Thor agent versions 3.4.2 and before 3.7.0 on Windows, allows attackers to bypass…
CVE-2026-25547 — Critical (CVSS 9.2): @isaacs/brace-expansion is a hybrid CJS/ESM TypeScript fork of brace-expansion. Prior to version 5.0.1,…
CVE-2023-29487 — Critical (CVSS 9.1): An issue was discovered in Heimdal Thor agent versions 3.4.2 and before on Windows and 2.6.9 and before on macOS,…
CVE-2026-47138 — High (CVSS 8.7): Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to…
CVE-2025-6998 — High (CVSS 8.7): ReDoS in strip_whitespaces() function in cps/string_helper.py in Calibre Web and Autocaliweb allows unauthenticated…

Browse all CWE-1333 vulnerabilities →