Malicious PDF — malware analysis report

Static analysis result for SHA-256 555b81e6c5c3f2e8…

MALICIOUS

PDF

60.8 KB Created: 2021-02-16 18:22:38 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 8564e41326a34a0238180e963256620f SHA-1: 225657592739f784471d9a5b4cf95dc378814002 SHA-256: 555b81e6c5c3f2e8a94a0c265d2d7b56b0f46d5f82dd0774e993cb37319ae3bf
96 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains an embedded URI pointing to a suspicious domain, likely intended to redirect the user to a phishing or malware distribution site. The document body, though heavily obfuscated, suggests a lure related to IELTS writing samples, indicating a phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 4

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://bologen.ru/strik?utm_term=ielts+general+writing+sample+questions+and+answers PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4503874/normal_5ffab339149eb.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369149/normal_60038fe647e84.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4369327/normal_5ffb6d543aa3b.pdfIn PDF document text
    • http://xufotegebiv.22web.org/sikefumejoxafoso.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382782/normal_5fd1434567eec.pdfIn PDF document text
    • https://cdn.sqhk.co/melukate/dhQghjg/are_hair_salons_open_in_los_angeles_today.pdfIn PDF document text
    • http://koburokigijufu.iblogger.org/zufewupuwogodev.pdfIn PDF document text
    • https://cdn.sqhk.co/melukate/LijeSMI/air_hockey_game_app_store.pdfIn PDF document text
    • https://cdn.sqhk.co/xusovatovu/Liaiage/77225542526.pdfIn PDF document text
    • https://cdn.sqhk.co/dezorevukor/dghhgij/fight_up_io_game.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4375522/normal_5fe671ad1dad4.pdfIn PDF document text
    • https://cdn.sqhk.co/xejudawadoni/8hikicV/carrageenan_allergy_in_cats.pdfIn PDF document text
    • https://cdn.sqhk.co/gexopoku/e8Eghjj/dirt_drift_zones_horizon_4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xupoguva.rf.gd/adobe_illustrator_for_windows.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b5e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5E7 5436 bytes
SHA-256: 46790bc59f58849c8408365c75d0bd2c39c74fb56e304c7420f9913b9d6c1f25
font_01_sfnt_off0000c855.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC855 8708 bytes
SHA-256: e70a61197f23f9959d316b3656b6499784a8fd479f29b2fbacd7ef16bb22da6c