How severe is CVE-2023-27530?

CVE-2023-27530 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-2023-27530 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27530?

CVE-2023-27530 primarily affects Rack. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-27530?

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-2023-27530 published?

CVE-2023-27530 was published on 2023-03-10 and last updated on 2026-10-24.

CVE-2023-27530

CVE-2023-27530 is a high-severity vulnerability in Rack 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-770.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 2% (79th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-770
Affected product: Rack
Published: 2023-03-10
Last modified: 2026-10-24

Description

A DoS vulnerability exists in Rack <v3.0.4.2, <v2.2.6.3, <v2.1.4.3 and <v2.0.9.3 within in the Multipart MIME parsing code in which could allow an attacker to craft requests that can be abuse to cause multipart parsing to take longer than expected.

Frequently asked questions

What is CVE-2023-27530?: A DoS vulnerability exists in Rack <v3.0.4.2, <v2.2.6.3, <v2.1.4.3 and <v2.0.9.3 within in the Multipart MIME parsing code in which could allow an attacker to craft requests that can be abuse to cause multipart parsing to take longer than expected.
How severe is CVE-2023-27530?: CVE-2023-27530 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-2023-27530 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (79th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27530?: CVE-2023-27530 primarily affects Rack. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-27530?: 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-2023-27530 published?: CVE-2023-27530 was published on 2023-03-10 and last updated on 2026-10-24.

References

Affected products (3)

cpe:2.3:a:rack:rack:*:*:*:*:*:ruby:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

More vulnerabilities in Rack

CVE-2026-34827 — High (CVSS 7.5): Rack is a modular Ruby web server interface. From versions 3.0.0.beta1 to before 3.1.21, and 3.2.0 to before 3.2.6,…
CVE-2026-34829 — High (CVSS 7.5): Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Multipart::Parser only…
CVE-2026-34785 — High (CVSS 7.5): Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Static determines…
CVE-2026-22860 — High (CVSS 7.5): Rack is a modular Ruby web server interface. Prior to versions 2.2.22, 3.1.20, and 3.2.5, `Rack::Directory`’s path…
CVE-2025-61919 — High (CVSS 7.5): Rack is a modular Ruby web server interface. Prior to versions 2.2.20, 3.1.18, and 3.2.3, `Rack::Request#POST` reads…
CVE-2025-61772 — High (CVSS 7.5): Rack is a modular Ruby web server interface. In versions prior to 2.2.19, 3.1.17, and 3.2.2, `Rack::Multipart::Parser`…

All CVEs affecting Rack →

Other CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities

CVE-2026-63299 — Critical (CVSS 9.9): An authorization bypass vulnerability in LXD allows an authenticated user to bypass project-level disk and volume…
CVE-2026-112779 — Critical (CVSS 9.8): Grav API plugin (grav-plugin-api) 1.0.40 before 1.0.42 caches a full translation dictionary for every well-formed…
CVE-2026-82439 — Critical (CVSS 9.8): Description The DRPC server kept a map from function name to request queue and created an entry the first time…
CVE-2026-47891 — Critical (CVSS 9.8): A Spring WebFlux application that relies on the Aalto XML processor to parse XML input does not correctly enforce the…
CVE-2026-74878 — Critical (CVSS 9.8): openssl_encrypt versions before 1.4.0 use an in-memory rate limiter for TOTP brute-force protection that is not shared…
CVE-2026-31283 — Critical (CVSS 9.8): In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email…

Browse all CWE-770 (Allocation of Resources Without Limits or Throttling) vulnerabilities →