Malicious PDF — malware analysis report

Static analysis result for SHA-256 87553b1ebbc8b637…

MALICIOUS

PDF

80.5 KB Created: 2021-03-24 10:52:34 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: e81d967aa817a3c4ac9ff53a1605f631 SHA-1: d4268a13e3005d90b53433be299cc1242c48875a SHA-256: 87553b1ebbc8b6374786008b501ae0392c608fe32bdfa723998405c27cfc2aba
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting or suspicious domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document's structure and numerous external links align with techniques used to obscure malicious destinations.

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
  • 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://ponafet.ru/award?keyword=bppv+exercises+epley+pdf PDF link annotation
    • http://pornbustyvids.com/extremespeed_dratini_quiz_answersosr2k.pdfIn PDF document text
    • http://heliusdesign.ru/32397290764laajf.pdfIn PDF document text
    • https://cdn.sqhk.co/wodaximewule/fijgdmg/aamc_msar_free.pdfIn PDF document text
    • https://cdn.sqhk.co/derebeduno/heIifMN/95262800372.pdfIn PDF document text
    • http://cardio-natural.info/3955529433njydb.pdfIn PDF document text
    • http://tinubawolu.mywebcommunity.org/zezifezabobo.pdfIn PDF document text
    • http://mizizufiku.mywebcommunity.org/17852485111.pdfIn PDF document text
    • https://cdn.sqhk.co/zenegiwowi/ke6hfIC/wilefo.pdfIn PDF document text
    • https://cdn.sqhk.co/putizimetiwe/QXkgdgd/rust_server_offline.pdfIn PDF document text
    • http://mebovaduzi.mywebcommunity.org/58731676764.pdfIn PDF document text
    • https://cdn.sqhk.co/fudimesa/bgcjbYA/frida_ios_dump_tutorial.pdfIn PDF document text
    • http://help-lnstagramcopyrights-verify.com/88351987410hyyzk.pdfIn PDF document text
    • https://cdn.sqhk.co/gosuzufus/7hbjajf/speedball_artista_pottery_wheel_legs.pdfIn PDF document text
    • https://cdn.sqhk.co/luwonowuwig/Z9bXidD/sejatiduxuzifekisirikefa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://d5e9a058-cbdc-4968-ba72-30cdbf1e36a3.filesusr.com/ugd/9cfd0a_4102c1aa18554dc7b10675d3e62e1431.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4b49ba7-81c1-41b1-9e5f-0b0dd7a6e771/how_to_configure_ncomputing_vspace_server.pdfIn PDF document text
    • https://5c90cfa9-af55-48e2-9430-1f3580382729.filesusr.com/ugd/e2b09b_8f13d293829a452b9a2ed190c80d7076.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/96cdf975-f210-4958-b45d-6af6513211ec/how_to_type_alpha_on_mac.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a69f852a-1a59-447c-ac44-b598fa8d4569/nesefazosevore.pdfIn PDF document text
    • http://wepogevadapafa.atwebpages.com/how_heavy_is_graco_snugride_35.pdfIn PDF document text
    • https://98771922-91e4-4673-aa0d-7794f4435593.filesusr.com/ugd/b6aaa0_f184582f66484c659575db9b3ac0a67a.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fdba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDBA 5220 bytes
SHA-256: d9b310ab9e3ad83d934b7a78d2fe1ddc73ba6617b2554228b4c5bba0a751b467
font_01_sfnt_off00010fa4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FA4 10536 bytes
SHA-256: 9d2e5918471acadd94c257396af388b045b96c8d8788757d2f59eadca5106bbf