Malicious PDF — malware analysis report

Static analysis result for SHA-256 57273e4ec8c4d408…

MALICIOUS

PDF

86.8 KB Created: 2021-04-03 20:52:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: cebdb960906b22a84d25b24424098408 SHA-1: e7f501cb18017320e94cf16d58f7c35aea58370c SHA-256: 57273e4ec8c4d408d29404bb5ffe6a93ba598fe3df8e2a70fd92c59d56815b28
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

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 0.9989

Heuristics 5

  • 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 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://bologen.ru/wix?keyword=algebra+2+a+final+exam+answer+key PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4381320/normal_5fd6e2c722662.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409799/normal_6031120e56d4b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451929/normal_601b44afeb6bb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379221/normal_600b46c416720.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4417519/normal_5fe03433a5f39.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495686/normal_60299019b8a8d.pdfIn PDF document text
    • https://cdn.sqhk.co/xeribaba/zhc0ja4/39826449446.pdfIn PDF document text
    • https://buzufurabobozu.weebly.com/uploads/1/3/5/3/135304208/32ea3cb5633770.pdfIn PDF document text
    • https://cdn.sqhk.co/xujutitula/OEZIhcL/zoriwuwepepotitefagavasi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4450350/normal_5ff2ba594a36f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4371004/normal_5febbe492d0af.pdfIn PDF document text
    • https://wekasekizoturir.weebly.com/uploads/1/3/4/1/134131482/foteluwujukol-pujepek-telekotogurev-jetuwu.pdfIn PDF document text
    • https://cdn.sqhk.co/veleviziwew/3cygdge/kodetajimux.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408997/normal_602d9449deb39.pdfIn PDF document text
    • http://zukasegepeni.22web.org/piditevapapiwusokov.pdfIn PDF document text
    • http://xoguvexebono.iblogger.org/christmas_cryptic_crossword_with_answers.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365659/normal_60354633adf3a.pdfIn PDF document text
    • https://cdn.sqhk.co/figakeves/AfdVhj6/kewojoxuzag.pdfIn PDF document text
    • https://xoxatazafej.weebly.com/uploads/1/3/4/8/134861408/tufosukaz.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://5071cc05-3fa2-46b1-b944-d2523ca4b51d.filesusr.com/ugd/62e2c1_4d25b079ec2645369ce38ba79edf37ea.pdf?index=trueIn PDF document text
    • https://7e005a1c-fb68-43c1-af83-b854b6a2d282.filesusr.com/ugd/dcfb95_3029c113a3b142f39b161072c5a53ef8.pdf?index=trueIn PDF document text
    • http://volajigatume.epizy.com/61291932938.pdfIn PDF document text
    • https://06e27459-8a58-4d01-a48e-f853eab966f6.filesusr.com/ugd/55f1a0_70a972841a514bd5aa46beba7c817d5c.pdf?index=trueIn PDF document text
    • https://80c93ba6-74df-4afb-9852-3a83eaba20e3.filesusr.com/ugd/4cf28d_89e0f09d1e104bfd87d87396d83e04ed.pdf?index=trueIn PDF document text
    • https://94aa8f26-b07a-4c24-bdb4-4112657565c9.filesusr.com/ugd/37428b_7c25a61f10514ccba1c1bd6d560197ca.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD2C 5672 bytes
SHA-256: 10c89a1aeab6aa7f42806b838b47d080efd17c1a727a7866fc4ccf3c315ab690
font_01_sfnt_off00011090.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11090 11388 bytes
SHA-256: 18c3fd256a1d1450d925a13f07592d2461fd5810838c95f3ec181c6be1dde23b
font_02_sfnt_off00013796.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13796 16160 bytes
SHA-256: 49898e49e877ec90855fa0b20ec776352fbbc9c6da67f9354d1218dc46407470