Malicious PDF — malware analysis report

Static analysis result for SHA-256 eebbd16616efa5ba…

MALICIOUS

PDF

88.5 KB Created: 2021-03-25 01:29:05 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: fec34c62435fdb70edb019e9c6b21d36 SHA-1: 18c3dc7a5dc4f6e4f99a6d5564af0120db3ee5a1 SHA-256: eebbd16616efa5bacc5080a2f534c7f36c501f130187145dbe7c23aa046dcec6
244 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF document was identified as malicious by multiple heuristics and a machine learning classifier, specifically flagging it as a redirector and a link farm. The embedded URLs, such as https://yafferge.ru/award?keyword=sample+of+job+letter+pdf, likely lead to phishing or malware download sites. The extensive link farm suggests an attempt to distribute malicious content broadly.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://yafferge.ru/award?keyword=sample+of+job+letter+pdf In PDF document text
    • https://mosiwiwemupal.weebly.com/uploads/1/3/1/3/131383889/zakarad.pdfIn PDF document text
    • https://govodiroruje.weebly.com/uploads/1/3/0/7/130775462/bunerifefiko-tenapiw-nufefodorevaxu-wibugeve.pdfIn PDF document text
    • https://katalajoguv.weebly.com/uploads/1/3/2/7/132740778/8417648.pdfIn PDF document text
    • https://rimedugomo.weebly.com/uploads/1/3/0/7/130740195/nuxivulupi.pdfIn PDF document text
    • http://fosegede.22web.org/noruxuzajofiwa.pdfIn PDF document text
    • https://vobudofokivelux.weebly.com/uploads/1/3/4/5/134599261/8536696.pdfIn PDF document text
    • https://jutawalafomas.weebly.com/uploads/1/3/4/3/134316275/817867.pdfIn PDF document text
    • https://jazigibebegada.weebly.com/uploads/1/3/1/6/131606339/faworalija-kemererejof-bibip-luxubodino.pdfIn PDF document text
    • https://fewefemuge.weebly.com/uploads/1/3/4/3/134372507/jevoto.pdfIn PDF document text
    • https://dalokagamamis.weebly.com/uploads/1/3/4/6/134695183/5895356.pdfIn PDF document text
    • https://wowajonaj.weebly.com/uploads/1/3/4/7/134717857/1732344.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://748e62c5-a849-4dff-87e7-3b5f74cb3522.filesusr.com/ugd/0df896_fa04f4321271448585f46c917561dd89.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/349051da-d616-4273-aaac-a781d8090bc0/discipline_and_punish_citation_harvard.pdfIn PDF document text
    • http://romajox.epizy.com/lipawedojobudafareku.pdfIn PDF document text
    • http://judumiji.epizy.com/kanuloxobazirapagibipefen.pdfIn PDF document text
    • https://538d8494-0c7d-401a-b890-0485f6bc7bca.filesusr.com/ugd/29c71c_b7d1c605cd094db38be5a98addc53e8b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a72e7924-abdd-4da3-9fff-9bc95bd52fa3/44106027170.pdfIn PDF document text
    • http://kabasefojegozaf.epizy.com/kituzonegu.pdfIn PDF document text
    • https://7e62deb9-9b1a-4e2d-8b60-9a8f762ee201.filesusr.com/ugd/1f553f_bf98dda4e5344ad9ab3fb748e47ccf83.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 PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010ea3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EA3 4960 bytes
SHA-256: a6ec2578821115476a076d3392451c79b7129722c1e52df3e80f6c3f6e6b6074
font_01_sfnt_off00011f7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F7E 11256 bytes
SHA-256: 766e2a1309050b652d7dff7f12341c769487e4b412cf0c48c7194bab2c22ac80
font_02_sfnt_off0001458e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1458E 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2