How severe is CVE-2018-20846?

CVE-2018-20846 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-20846 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20846?

CVE-2018-20846 affects Uclouvain Openjpeg. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-20846?

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

When was CVE-2018-20846 published?

CVE-2018-20846 was published on 2019-06-26 and last updated on 2026-06-17.

CVE-2018-20846

CVE-2018-20846 is a medium-severity vulnerability in Uclouvain Openjpeg with a CVSS 3.x base score of 6.5. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 4.3
EPSS exploit prediction: 2% (80th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Uclouvain Openjpeg
Published: 2019-06-26
Last modified: 2026-06-17

Description

Out-of-bounds accesses in the functions pi_next_lrcp, pi_next_rlcp, pi_next_rpcl, pi_next_pcrl, pi_next_rpcl, and pi_next_cprl in openmj2/pi.c in OpenJPEG through 2.3.0 allow remote attackers to cause a denial of service (application crash).

Frequently asked questions

What is CVE-2018-20846?: Out-of-bounds accesses in the functions pi_next_lrcp, pi_next_rlcp, pi_next_rpcl, pi_next_pcrl, pi_next_rpcl, and pi_next_cprl in openmj2/pi.c in OpenJPEG through 2.3.0 allow remote attackers to cause a denial of service (application crash).
How severe is CVE-2018-20846?: CVE-2018-20846 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-20846 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (80th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20846?: CVE-2018-20846 affects Uclouvain Openjpeg. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-20846?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-20846 published?: CVE-2018-20846 was published on 2019-06-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:uclouvain:openjpeg:*:*:*:*:*:*:*:*

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