Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f09635ab18fbc92…

MALICIOUS

PDF

77.7 KB Created: 2021-03-23 03:52:25 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 1caf281eb0d96ed9221b5af3557d7f3e SHA-1: 59262fb6cec02e505c48183131b1f3db3d9374f4 SHA-256: 4f09635ab18fbc922a31869b5a21af5dfff1dc566d3887c686667a01b14b3514
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://golowaki.ru/award?keyword=categories+of+disabilities+pdf PDF link annotation
    • http://academic-club.ru/tolexomagfpd4d.pdfIn PDF document text
    • https://xegadoponuxi.weebly.com/uploads/1/3/0/7/130775279/sutesupurelum-nasazulosiji-lezeziraxosun-zutarunobe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4370996/normal_5fc8fbaabd188.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368506/normal_60241857ef4ba.pdfIn PDF document text
    • http://xazoxaruxilovo.iblogger.org/foolish_heart_steve_perry.pdfIn PDF document text
    • https://bigufoxorifef.weebly.com/uploads/1/3/1/8/131871864/julefuxagowadi-foxeti-gomamijidaxaxu.pdfIn PDF document text
    • https://fomunova.weebly.com/uploads/1/3/4/6/134684458/kudofezemaluj.pdfIn PDF document text
    • http://sudebatuwilazet.iblogger.org/78424092679.pdfIn PDF document text
    • https://lefusavuforuv.weebly.com/uploads/1/3/4/4/134490278/lijelugobasip.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4460944/normal_5ff16cd88a502.pdfIn PDF document text
    • http://lnstagram-copyright-confirms.com/21299167088vluye.pdfIn PDF document text
    • http://optamorem.com/xizoga1cmcw.pdfIn PDF document text
    • http://reduslim-shopofficial.site/rezofaxafajirejuw4os6u.pdfIn PDF document text
    • https://diwijavel.weebly.com/uploads/1/3/4/6/134691177/dadef.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4421615/normal_5ff03d52ee6ea.pdfIn PDF document text
    • https://kigekasomek.weebly.com/uploads/1/3/4/5/134598498/rewugubozuwogesebadi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371005/normal_5fef653d90894.pdfIn PDF document text
    • http://godevibusaxinoj.22web.org/jipejirijata.pdfIn PDF document text
    • http://www.ascendercorp.com/In extracted file (font_00_sfnt_off0000f380.bin)
    • http://www.ascendercorp.com/typedesigners.htmlIn extracted file (font_00_sfnt_off0000f380.bin)
    • http://zakusomob.rf.gd/nomogatamol.pdfIn PDF document text
    • https://cae2aa39-5014-47ec-b549-0fed73f36d02.filesusr.com/ugd/c8683e_a2e595ca346f4c0fa326b3ed7768e916.pdf?index=trueIn PDF document text
    • http://ruxuvejefo.epizy.com/free_template_joomla_quickstart.pdfIn PDF document text
    • https://0793e221-2e7e-4176-aae8-4ff4b75d8f7a.filesusr.com/ugd/64bd79_0bdcb8f8b25f4744898e806ea1c337df.pdf?index=trueIn PDF document text
    • https://121f8fc1-d270-4171-a721-8ccd656fc20f.filesusr.com/ugd/2ca22b_f6581129ff9b48f2bb34ee700fb30a3e.pdf?index=trueIn PDF document text
    • https://51956041-da35-40aa-96c1-085c1f47c80d.filesusr.com/ugd/e6e573_96476d17e93440009d13e453859ddcfe.pdf?index=trueIn 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 extracted file (font_00_sfnt_off0000f380.bin)

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f380.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF380 5256 bytes
SHA-256: a3e517535872ac0a1007b61c714a4d107136b628a23ccc91445d8b1bb6689ca3
font_01_sfnt_off00010564.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10564 10412 bytes
SHA-256: f6adadba37276b1d9b17bc3e812ee4844ef4b6df4f30205869b5047a16623d58