CVE-2017-7771 [High] | Out-of-bounds Read in Firefox

CVE-2017-7771 is rated High Exploit Risk (70.9/100): CVSS High severity, with medium exploitation likelihood (EPSS 0.54%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

EDB-ID	Source	Kind	Published	Link
—	nvd_ref	exploit_tag		Exploit-DB ↗

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Published

Link

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Exploit-DB ↗

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-01-14	0.44%	0.54%	+0.10%
2	2025-03-30	1.39%	0.44%	-0.95%
3	2025-03-29	—	1.39%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-01-14

0.44%

0.54%

+0.10%

2025-03-30

1.39%

0.44%

-0.95%

2025-03-29

—

1.39%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.1	3.0	HIGH	`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H` Click to expand Attack vector (AV:N) Could be attacked over the internet or any normal routed network—not just someone sitting at the machine. Attack complexity (AC:L) Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:N) Data isn’t meaningfully altered or forged. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	2.8	5.2	[email protected]
5.8	2.0	MEDIUM	`AV:N/AC:M/Au:N/C:P/I:N/A:P` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:M) Exploitation needs some favorable conditions, but not exceptional ones. Authentication (AU:N) No authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:N) No integrity impact. Availability impact (A:P) Partial availability impact.	8.6	4.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.1

3.0

HIGH

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H Click to expand

Attack vector (AV:N): Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L): Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:N): Data isn’t meaningfully altered or forged.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

2.8

5.2

[email protected]

5.8

2.0

MEDIUM

AV:N/AC:M/Au:N/C:P/I:N/A:P Click to expand

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:M): Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:N): No integrity impact.
Availability impact (A:P): Partial availability impact.

8.6

4.9

[email protected]

OS Trackers for CVE-2017-7771

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2017-7771 not yet assigned priority: Debian including 3 source packages (firefox, firefox-esr, graphite2), 11 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 11.	https://security-tracker.debian.org/tracker/CVE-2017-7771
`gentoo`	high	CVE-2017-7771: 2 GLSA(s) (201710-13, 201802-03), 3 atom(s) (media-gfx/graphite2, www-client/firefox, www-client/firefox-bin); latest impact high.	https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2017-7771
`redhat`	low	—	https://access.redhat.com/security/cve/CVE-2017-7771
`suse`	high	CVE-2017-7771 severity important: SUSE including 76 source package names (MozillaFirefox, MozillaFirefox-102.11.0-150200.152.87.1, …), 118 product×package rows across 34 product lines (SUSE CaaS Platform 4.0, SUSE Enterprise Storage 6, … (34 product lines)): Fixed 84, Known Not Affected 34.	https://www.suse.com/security/cve/CVE-2017-7771/
`ubuntu`	medium	CVE-2017-7771 medium priority: Ubuntu including 3 source packages (firefox, graphite2, thunderbird), 15 status rows across 5 suites (trusty, upstream, xenial, yakkety, zesty): released 14, ignored 1.	https://ubuntu.com/security/CVE-2017-7771

Affected software / configurations for CVE-2017-7771

Vendor	Product	Version	Raw CPE
mozilla	firefox	< 54.0	cpe:2.3:a:mozilla:firefox::::::::
sil	graphite2	< 1.3.10	cpe:2.3:a:sil:graphite2::::::::

References for CVE-2017-7771

URL	Tags
https://www.mozilla.org/en-US/security/advisories/mfsa2017-15/	Exploit Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1472212	Third Party Advisory

URL

CVE-2017-7771

Public exploit references (Exploit-DB) for CVE-2017-7771

Exploit prediction scoring system (EPSS) score for CVE-2017-7771

Common vulnerability scoring system (CVSS) metrics for CVE-2017-7771

Weakness enumeration for CVE-2017-7771

OS Trackers for CVE-2017-7771

Affected software / configurations for CVE-2017-7771

References for CVE-2017-7771