How severe is CVE-2018-21232?

CVE-2018-21232 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-21232 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-21232?

CVE-2018-21232 affects Re2c. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-21232?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-21232 published?

CVE-2018-21232 was published on 2020-04-29 and last updated on 2026-06-17.

CVE-2018-21232

CVE-2018-21232 is a medium-severity vulnerability in Re2c with a CVSS 3.x base score of 5.5. 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-674.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-674
Affected product: Re2c
Published: 2020-04-29
Last modified: 2026-06-17

Description

re2c before 2.0 has uncontrolled recursion that causes stack consumption in find_fixed_tags.

Frequently asked questions

What is CVE-2018-21232?: re2c before 2.0 has uncontrolled recursion that causes stack consumption in find_fixed_tags.
How severe is CVE-2018-21232?: CVE-2018-21232 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-21232 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-21232?: CVE-2018-21232 affects Re2c. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-21232?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-21232 published?: CVE-2018-21232 was published on 2020-04-29 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:re2c:re2c:*:*:*:*:*:*:*:*

More vulnerabilities in Re2c

CVE-2022-23901 — Critical (CVSS 9.8): A stack overflow re2c 2.2 exists due to infinite recursion issues in src/dfa/dead_rules.cc.
CVE-2020-11958 — High (CVSS 7.8): re2c 1.3 has a heap-based buffer overflow in Scanner::fill in parse/scanner.cc via a long lexeme.

All CVEs affecting Re2c →

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CVE-2021-41752 — Critical (CVSS 9.8): Stack overflow vulnerability in Jerryscript before commit e1ce7dd7271288be8c0c8136eea9107df73a8ce2 on Oct 20, 2021 due…
CVE-2018-1000618 — Critical (CVSS 9.8): EOSIO/eos eos version after commit f1545dd0ae2b77580c2236fdb70ae7138d2c7168 contains a stack overflow vulnerability in…
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