Malicious PDF — malware analysis report

Static analysis result for SHA-256 c659f5f8dae227a2…

MALICIOUS

PDF

70.4 KB Created: 2020-11-14 16:53:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a51661d06da3276858d2480caf560c1b SHA-1: 196d937e42f85d1e7a2502deda7aefc91ae11553 SHA-256: c659f5f8dae227a21f4171d3dda11c335d28e3b661ce2ce93aa94dd8cf9c74c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains heuristics indicating it is a phishing or malicious document, with ML classifiers and ClamAV flagging it as such. It embeds external URIs, notably directing to 'traffset.ru', which is likely part of a phishing or malware distribution scheme. The document body, though heavily obfuscated, suggests a lure related to "cryptic maths quiz questions" to entice users to click on the malicious link.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://traffset.ru/123?utm_term=cryptic+maths+quiz+questions
    • https://viwuwobigoku.weebly.com/uploads/1/3/1/3/131378942/besorutufimoja.pdf
    • https://vumevomuw.weebly.com/uploads/1/3/4/3/134335884/4714d872f13b.pdf
    • https://xusawoji.weebly.com/uploads/1/3/0/7/130739635/efccba.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/belapawerezuju/pellon_fusible_interfacing.pdf
    • https://uploads.strikinglycdn.com/files/557fddef-8a9a-4862-839e-541b908b07ff/harley_merlin_books_series.pdf
    • https://s3.amazonaws.com/bofake/squier_strat_wiring_kit.pdf
    • https://uploads.strikinglycdn.com/files/4db9df3f-6649-4b5c-a6f8-9689d5b48b70/mobaxusakeponiz.pdf
    • https://s3.amazonaws.com/memul/jitutomuzotademokuzojilun.pdf
    • https://s3.amazonaws.com/xanebavifamopez/55440352506.pdf
    • https://s3.amazonaws.com/nuruvapozixix/sofelumazoxapipajada.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c79c.bin
c2e8d1e4afa99229609611b483c0d39141ec949f38f4e08d3e33614df42c862c
pdf-font-stream PDF embedded font (sfnt) at offset 0xC79C 5324 bytes
font_01_sfnt_off0000d99f.bin
9628a1836bd32f1061484997f3ca406b590e1925d3bbf42ddacb4aead629d425
pdf-font-stream PDF embedded font (sfnt) at offset 0xD99F 10964 bytes
font_02_sfnt_off0000fed4.bin
a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFED4 4324 bytes