How severe is CVE-2018-20783?

CVE-2018-20783 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 high, integrity none, and availability none.

Is CVE-2018-20783 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-20783?

CVE-2018-20783 primarily affects Php. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-20783?

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-2018-20783 published?

CVE-2018-20783 was published on 2019-02-21 and last updated on 2026-06-17.

CVE-2018-20783

CVE-2018-20783 is a high-severity vulnerability in Php 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 6% (92nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Php
Published: 2019-02-21
Last modified: 2026-06-17

Description

In PHP before 5.6.39, 7.x before 7.0.33, 7.1.x before 7.1.25, and 7.2.x before 7.2.13, a buffer over-read in PHAR reading functions may allow an attacker to read allocated or unallocated memory past the actual data when trying to parse a .phar file. This is related to phar_parse_pharfile in ext/phar/phar.c.

Frequently asked questions

What is CVE-2018-20783?: In PHP before 5.6.39, 7.x before 7.0.33, 7.1.x before 7.1.25, and 7.2.x before 7.2.13, a buffer over-read in PHAR reading functions may allow an attacker to read allocated or unallocated memory past the actual data when trying to parse a .phar file. This is related to phar_parse_pharfile in ext/phar/phar.c.
How severe is CVE-2018-20783?: CVE-2018-20783 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 high, integrity none, and availability none.
Is CVE-2018-20783 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (92nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-20783?: CVE-2018-20783 primarily affects Php. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-20783?: 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-2018-20783 published?: CVE-2018-20783 was published on 2019-02-21 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:php:php:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:42.3:*:*:*:*:*:*:*

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Other CWE-125 (Out-of-bounds Read) vulnerabilities

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CVE-2021-41556 — Critical (CVSS 10.0): sqclass.cpp in Squirrel through 2.2.5 and 3.x through 3.1 allows an out-of-bounds read (in the core interpreter) that…
CVE-2021-21777 — Critical (CVSS 10.0): An information disclosure vulnerability exists in the Ethernet/IP UDP handler functionality of EIP Stack Group OpENer…
CVE-2017-14451 — Critical (CVSS 10.0): An exploitable out-of-bounds read vulnerability exists in libevm (Ethereum Virtual Machine) of CPP-Ethereum. A…
CVE-2013-0767 — Critical (CVSS 10.0): The nsSVGPathElement::GetPathLengthScale function in Mozilla Firefox before 18.0, Firefox ESR 10.x before 10.0.12 and…

Browse all CWE-125 (Out-of-bounds Read) vulnerabilities →

Threat intelligence

Threat-intel indicators referencing this CVE:

45.84.120.3 (ipv4-addr)
79.137.34.248 (ipv4-addr)
221.161.235.168 (ipv4-addr)
200.196.50.91 (ipv4-addr)
187.51.208.158 (ipv4-addr)
187.141.71.166 (ipv4-addr)
187.110.238.50 (ipv4-addr)
182.93.50.90 (ipv4-addr)