How severe is CVE-2016-1833?

CVE-2016-1833 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-2016-1833 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-1833?

CVE-2016-1833 primarily affects Apple Iphone Os. In total, 29 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-1833?

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

When was CVE-2016-1833 published?

CVE-2016-1833 was published on 2016-05-20 and last updated on 2026-06-17.

CVE-2016-1833

CVE-2016-1833 is a medium-severity vulnerability in Apple Iphone Os 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-125.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 4.3
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Apple Iphone Os
Published: 2016-05-20
Last modified: 2026-06-17

Description

The htmlCurrentChar function in libxml2 before 2.9.4, as used in Apple iOS before 9.3.2, OS X before 10.11.5, tvOS before 9.2.1, and watchOS before 2.2.1, allows remote attackers to cause a denial of service (heap-based buffer over-read) via a crafted XML document.

Frequently asked questions

What is CVE-2016-1833?: The htmlCurrentChar function in libxml2 before 2.9.4, as used in Apple iOS before 9.3.2, OS X before 10.11.5, tvOS before 9.2.1, and watchOS before 2.2.1, allows remote attackers to cause a denial of service (heap-based buffer over-read) via a crafted XML document.
How severe is CVE-2016-1833?: CVE-2016-1833 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-2016-1833 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-1833?: CVE-2016-1833 primarily affects Apple Iphone Os. In total, 29 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-1833?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-1833 published?: CVE-2016-1833 was published on 2016-05-20 and last updated on 2026-06-17.

References

Affected products (29)

cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:12.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:15.10:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.2:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.3:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_aus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.2:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.3:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.5:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_eus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_tus:7.2:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_tus:7.3:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_server_tus:7.6:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_workstation:7.0:*:*:*:*:*:*:*
cpe:2.3:a:xmlsoft:libxml2:*:*:*:*:*:*:*:*
cpe:2.3:a:mcafee:web_gateway:*:*:*:*:*:*:*:*

More vulnerabilities in Apple Iphone Os

CVE-2025-43300 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS…
CVE-2025-24201 — Critical (CVSS 10.0): An out-of-bounds write issue was addressed with improved checks to prevent unauthorized actions. This issue is fixed in…
CVE-2025-24085 — Critical (CVSS 10.0): A use after free issue was addressed with improved memory management. This issue is fixed in iOS 18.3 and iPadOS 18.3,…
CVE-2022-32845 — Critical (CVSS 10.0): This issue was addressed with improved checks. This issue is fixed in watchOS 8.7, iOS 15.6 and iPadOS 15.6, macOS…
CVE-2019-8779 — Critical (CVSS 10.0): A logic issue applied the incorrect restrictions. This issue was addressed by updating the logic to apply the correct…
CVE-2018-4310 — Critical (CVSS 10.0): An access issue was addressed with additional sandbox restrictions. This issue affected versions prior to iOS 12, macOS…

All CVEs affecting Apple Iphone Os →

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

CVE-2026-24826 — Critical (CVSS 10.0): Out-of-bounds Write, Divide By Zero, NULL Pointer Dereference, Use of Uninitialized Resource, Out-of-bounds Read,…
CVE-2024-22004 — Critical (CVSS 10.0): Due to length check, an attacker with privilege access on a Linux Nonsecure operating system can trigger a…
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 →