libical 1.0 allows remote attackers to cause a denial of service (use-after-free) via a crafted ics file.
- Published
- Jan 27, 2017
- Updated
- Jun 16, 2026
- EPSS
- 2.2% · 82th percentile
- CWE
- CWE-416
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Report tools
Action score
23
Monitor
Low priority for now.
- CVSS
- 22 / 40 · 5.5 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 1 / 30 · 2.2%
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| libical project | libical | cpe:2.3:a:libical_project:libical |
| canonical | ubuntu linux | cpe:2.3:o:canonical:ubuntu_linux |
| redhat | enterprise linux desktop | cpe:2.3:o:redhat:enterprise_linux_desktop |
| redhat | enterprise linux server | cpe:2.3:o:redhat:enterprise_linux_server |
| redhat | enterprise linux server aus | cpe:2.3:o:redhat:enterprise_linux_server_aus |
| redhat | enterprise linux server eus | cpe:2.3:o:redhat:enterprise_linux_server_eus |
| redhat | enterprise linux server tus | cpe:2.3:o:redhat:enterprise_linux_server_tus |
| redhat | enterprise linux workstation | cpe:2.3:o:redhat:enterprise_linux_workstation |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- canonical ubuntu linux14.04
- canonical ubuntu linux16.04
- canonical ubuntu linux18.04
- canonical ubuntu linux18.10
- libical project libical1.0
- redhat enterprise linux desktop6.0
- redhat enterprise linux desktop7.0
- redhat enterprise linux server6.0
- redhat enterprise linux server7.0
- redhat enterprise linux server aus7.6
- redhat enterprise linux server eus7.6
- redhat enterprise linux server tus7.6
- redhat enterprise linux workstation6.0
- redhat enterprise linux workstation7.0
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | thunderbird | before 1:60.5.0-1 | 1:60.5.0-1 |
| Debian:7 | libical | before 0.48-2+deb7u1 | 0.48-2+deb7u1 |
| Red Hat:enterprise_linux:6::client | thunderbird | before 0:60.5.0-1.el6_10 | 0:60.5.0-1.el6_10 |
| Red Hat:enterprise_linux:6::client | thunderbird-debuginfo | before 0:60.5.0-1.el6_10 | 0:60.5.0-1.el6_10 |
| Red Hat:enterprise_linux:7::client | thunderbird | before 0:60.5.0-1.el7_6 | 0:60.5.0-1.el7_6 |
| Red Hat:enterprise_linux:7::client | thunderbird-debuginfo | before 0:60.5.0-1.el7_6 | 0:60.5.0-1.el7_6 |
| SUSE:Linux Enterprise Desktop 12 SP2 | libical | before 1.0.1-16.3.1 | 1.0.1-16.3.1 |
| SUSE:Linux Enterprise Software Development Kit 11 SP4 | libical | before 0.43-1.10.6.1 | 0.43-1.10.6.1 |
| SUSE:Linux Enterprise Workstation Extension 15 | MozillaThunderbird | before 60.5.0-3.20.2 | 60.5.0-3.20.2 |
| SUSE:Package Hub 12 | MozillaThunderbird | before 60.5.1-79.1 | 60.5.1-79.1 |
Same product
libical project: all recordsOther highest-scoring records for the same primary product.
- CVE-2016-9584libical allows remote attackers to cause a denial of service (use-after-free) and possibly read heap memory via a crafted ics file.37Monitor
- CVE-2016-5827The icaltime_from_string function in libical 0.47 and 1.0 allows remote attackers to cause a denial of service (out-of-bounds heap read) via31Monitor
- CVE-2016-5826The parser_get_next_char function in libical 0.47 and 1.0 allows remote attackers to cause a denial of service (out-of-bounds heap read) by 31Monitor
- CVE-2016-5825The icalparser_parse_string function in libical 0.47 and 1.0 allows remote attackers to cause a denial of service (out-of-bounds heap read) 22Monitor
- CVE-2016-5823The icalproperty_new_clone function in libical 0.47 and 1.0 allows remote attackers to cause a denial of service (use-after-free) via a craf22Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:libical | 0.48-2+deb7u1 · Debian:7 | Package registry (OSV) |
| debian:thunderbird | 1:60.5.0-1 · Debian:12 | Package registry (OSV) |
| red hat:thunderbird | 0:60.5.0-1.el6_10 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| red hat:thunderbird-debuginfo | 0:60.5.0-1.el6_10 · Red Hat:enterprise_linux:6::client | Package registry (OSV) |
| suse:libical | 1.0.1-16.3.1 · SUSE:Linux Enterprise Desktop 12 SP2 | Package registry (OSV) |
| suse:MozillaThunderbird | 60.5.0-3.20.2 · SUSE:Linux Enterprise Workstation Extension 15 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- No account or password is required.
- A user must open a link or visit a page.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- none
- Integrity
- none
- Availability
- high · the service can be disrupted
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality impact
- None
- Integrity impact
- None
- Availability impact
- High
Weakness class (CWE)
CWE-416 · Use After FreeCVSS vector
CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
nvd-primary
Root cause
After a memory region is freed, another reference pointing to it is still used. By then, the same region may have been allocated for different data.
The bug in code
The whole CWE-416 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
free(dev->buf);/* ... another thread is still running ... */process(dev->buf);Fixed
lock(&dev->lock);free(dev->buf);dev->buf = NULL;unlock(&dev->lock);Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
MITRE has no CAPEC/ATT&CK mapping for this CWE.
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
- www.openwall.com/lists/oss-security/2016/06/25/4
- www.openwall.com/lists/oss-security/2017/01/20/16
- www.securityfocus.com/bid/91459
- access.redhat.com/errata/RHSA-2019:0269
- access.redhat.com/errata/RHSA-2019:0270
- bugzilla.mozilla.org/show_bug.cgi?id=1275400
- github.com/libical/libical/issues/235
- github.com/libical/libical/issues/251
- github.com/libical/libical/issues/286
- security.gentoo.org/glsa/201904-02
- security.gentoo.org/glsa/201904-07
- usn.ubuntu.com/3897-1/
Vendor advisories and official records. Exploit/PoC links are deliberately left out.