How severe is CVE-2021-27345?

CVE-2021-27345 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-2021-27345 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27345?

CVE-2021-27345 primarily affects Long Range Zip Project Long Range Zip. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-27345?

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

When was CVE-2021-27345 published?

CVE-2021-27345 was published on 2021-06-10 and last updated on 2026-06-17.

CVE-2021-27345

CVE-2021-27345 is a medium-severity vulnerability in Long Range Zip Project Long Range Zip 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-476.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-476
Affected product: Long Range Zip Project Long Range Zip
Published: 2021-06-10
Last modified: 2026-06-17

Description

A null pointer dereference was discovered in ucompthread in stream.c in Irzip 0.631 which allows attackers to cause a denial of service (DOS) via a crafted compressed file.

Frequently asked questions

What is CVE-2021-27345?: A null pointer dereference was discovered in ucompthread in stream.c in Irzip 0.631 which allows attackers to cause a denial of service (DOS) via a crafted compressed file.
How severe is CVE-2021-27345?: CVE-2021-27345 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-2021-27345 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27345?: CVE-2021-27345 primarily affects Long Range Zip Project Long Range Zip. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-27345?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27345 published?: CVE-2021-27345 was published on 2021-06-10 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:long_range_zip_project:long_range_zip:0.631:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

More vulnerabilities in Long Range Zip Project Long Range Zip

CVE-2018-10685 — Critical (CVSS 9.8): In Long Range Zip (aka lrzip) 0.631, there is a use-after-free in the lzma_decompress_buf function of stream.c, which…
CVE-2021-33453 — High (CVSS 7.8): An issue was discovered in lrzip version 0.641. There is a use-after-free in ucompthread() in stream.c:1538.
CVE-2017-8844 — High (CVSS 7.8): The read_1g function in stream.c in liblrzip.so in lrzip 0.631 allows remote attackers to cause a denial of service…
CVE-2018-11496 — Medium (CVSS 6.5): In Long Range Zip (aka lrzip) 0.631, there is a use-after-free in read_stream in stream.c, because decompress_file in…
CVE-2023-39741 — Medium (CVSS 5.5): lrzip v0.651 was discovered to contain a heap overflow via the libzpaq::PostProcessor::write(int) function at…
CVE-2021-33451 — Medium (CVSS 5.5): An issue was discovered in lrzip version 0.641. There are memory leaks in fill_buffer() in stream.c.

All CVEs affecting Long Range Zip Project Long Range Zip →

Other CWE-476 (NULL Pointer Dereference) vulnerabilities

CVE-2022-36648 — Critical (CVSS 10.0): The hardware emulation in the of_dpa_cmd_add_l2_flood of rocker device model in QEMU, as used in 7.0.0 and earlier,…
CVE-2020-14500 — Critical (CVSS 10.0): Secomea GateManager all versions prior to 9.2c, An attacker can send a negative value and overwrite arbitrary data.
CVE-2010-2495 — Critical (CVSS 10.0): The pppol2tp_xmit function in drivers/net/pppol2tp.c in the L2TP implementation in the Linux kernel before 2.6.34 does…
CVE-2026-46195 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: smb: client: validate dacloffset before building…
CVE-2026-31657 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: batman-adv: hold claim backbone gateways by…
CVE-2026-31436 — Critical (CVSS 9.8): In the Linux kernel, the following vulnerability has been resolved: dmaengine: idxd: fix possible wrong descriptor…

Browse all CWE-476 (NULL Pointer Dereference) vulnerabilities →