Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8ac5c831f60a2e1…

MALICIOUS

PDF

86.3 KB Created: 2021-02-24 22:34:17 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 55543a22e7a7df28c6b5c8da9fceadf8 SHA-1: 694056296bf65044e5c0c1b9067d91c79cf22701 SHA-256: d8ac5c831f60a2e17d4b23e8d4bcbf60b39c922bc05dc483ea582e096c090e7e
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to Weebly-hosted PDFs with numeric slugs, indicative of a link farm or SEO spam campaign. One of the primary URLs, 'https://seumenha.ru/award?keyword=all+my+sons+short+summary+pdf', suggests a lure to a specific search result. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://seumenha.ru/award?keyword=all+my+sons+short+summary+pdf
    • https://feronokemafa.weebly.com/uploads/1/3/1/1/131164109/ed5ec8ea6cdd.pdf
    • https://cdn-cms.f-static.net/uploads/4470552/normal_602b27c292a76.pdf
    • http://acupofjacob.com/onan_4000_microlite_generator_parts6noou.pdf
    • https://mimitokiwunas.weebly.com/uploads/1/3/4/0/134012498/fdbafa.pdf
    • https://linerebe.weebly.com/uploads/1/3/0/8/130813546/35a6d25f13228b.pdf
    • http://vubitim.sportsontheweb.net/85316318165.pdf
    • http://bebetadiruj.mywebcommunity.org/whats_another_word_for_sensei.pdf
    • https://jofevuwob.weebly.com/uploads/1/3/4/2/134235005/wofazaviguziw_vapugewoposi_bokepesusexar.pdf
    • http://wonnaturila.space/english_to_hindi_kruti_dev_010_onlinenj2b2.pdf
    • https://dosabaret.weebly.com/uploads/1/3/4/8/134861273/tofesefadim.pdf
    • http://wejuzofibab.medianewsonline.com/34994592242.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/vipuxafol/lake_arrowhead_fishing_report_2018.pdf
    • https://s3.amazonaws.com/rubidokezive/finudaperemezepe.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000117e0.bin
a6a8aa4fdbc0de7af37183edecf3163aa0fe84e6d201749fd1c0e393c1296165
pdf-font-stream PDF embedded font (sfnt) at offset 0x117E0 5372 bytes
font_01_sfnt_off00012a04.bin
e63ad8cce705035237f372e1b9fa82b6eb6231fa6b651339d0d73424a1668b74
pdf-font-stream PDF embedded font (sfnt) at offset 0x12A04 10000 bytes