Malicious PDF — malware analysis report

Static analysis result for SHA-256 91ae0e30ebeeb6ca…

MALICIOUS

PDF

9.4 KB
MD5: 696de8d1ab40370ae8b96948c6f0d8f7 SHA-1: f2f74ccbd316dd97b6844161300a0e37348a0ae7 SHA-256: 91ae0e30ebeeb6caf925d265a1f73fea571ce5052a25e8f43550a926a3c8d6cc
224 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious Link

The PDF file contains embedded JavaScript, triggered by the CVE-2007-5659 vulnerability related to 'collab.collectEmailInfo'. This JavaScript is heavily obfuscated and appears to be a stager, indicated by the 'annotation_subject_callee_hex_stage_000.js' and 'deobfuscated.js' artifacts. The primary function of this script is to download and execute a second-stage payload, as suggested by the heuristic firings and the nature of the extracted JavaScript.

Heuristics 7

  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV: Pdf.Dropper.Agent-7283035-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-7283035-0
  • Annotation subject callee-key hex JavaScript stager high PDF_ANNOT_SUBJECT_CALLEE_HEX_STAGER
    PDF JavaScript uses syncAnnotScan()/getAnnots() to read an indirect annotation /Subject stream, percent-decodes it through marker replacement, then uses a callee.toString()-derived key to decode and eval the final exploit stage.
  • Suspicious extracted artifact high EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • syncAnnotScan annotation-staging primitive low PDF_FOXIT_SYNCANNOTSCAN
    PDF JavaScript calls syncAnnotScan() — a no-op annotation-enumeration primitive used by exploit-kit JavaScript to stage payload reads from annotation /Subject fields before eval(). Not a vulnerable sink itself; rarely seen in legitimate PDFs. (matched in decompressed stream)

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0007_000.js
11b03694c4e705ab29873cc5e2c55342ee498b376ac2dc5f05ce17018ef44c38
pdf-javascript-stream PDF /JS object 7 at offset 0x19D 264 bytes
annotation_subject_callee_hex_stage_000.js
8522f53f1bbba00291fb7f55bcd77f6ec19570ca20dec0d86f54adb893bce754
deobfuscated-js annotation-subject callee-key decoded JavaScript at offset 0x14A 4992 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 5 eval/decoder/string-building token(s).
deobfuscated.js
f14cd74c1ef716b9a16816cccd7e82f82f97d43dff033a8d99b05175d247aa43
deobfuscated-js PDF JavaScript deobfuscation pass 67615 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 long base64-like blob(s).