Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc1c5b7625e8d3f8…

MALICIOUS

PDF

84.1 KB Created: 2021-04-07 21:03:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 19a99e0e4399afa0cf0fd61912eb689c SHA-1: 58ff6926df1c758911784dc0430744de6678e349 SHA-256: fc1c5b7625e8d3f871be7ae29046faf8391461249a35196e70762d181d01c164
194 Risk Score

Malware Insights

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

The sample is a PDF document identified as malicious by ClamAV and an ML classifier. It contains a large number of external links, many pointing to disposable hosting, indicating a link farm or phishing attempt. The document body is heavily obfuscated, but the presence of numerous external URIs and the 'PDF_SEO_LINK_FARM' heuristic strongly suggest the intent is to redirect users to malicious websites, likely for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://kuzutuzo.ru/aws?utm_term=how+hard+is+the+acsm+personal+trainer+exam PDF link annotation
    • http://bosnoslovnoejelaniekupit.xyz/fubuxudiladifinul8l3su.pdfIn PDF document text
    • https://xodimiteti.weebly.com/uploads/1/3/0/7/130776847/9688147.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392199/normal_5fec940dd5f09.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422134/normal_5fd96be442310.pdfIn PDF document text
    • https://vekupaju.weebly.com/uploads/1/3/4/4/134479754/9763009.pdfIn PDF document text
    • http://digtalcaliper09.xyz/integral_csc2_xhq9la.pdfIn PDF document text
    • http://sendgrid-de.com/110450399310w7n3.pdfIn PDF document text
    • https://judavolegarar.weebly.com/uploads/1/3/1/8/131871921/3902013.pdfIn PDF document text
    • http://form-lnstagramverificationbadge.com/form_144_amendmentp9w98.pdfIn PDF document text
    • https://nedixizudunosil.weebly.com/uploads/1/3/1/4/131483200/zenajug.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4503787/normal_602e37ae6d799.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455374/normal_603d1daee1ef6.pdfIn PDF document text
    • https://wuzafonufiza.weebly.com/uploads/1/3/4/3/134341979/5372145.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4481406/normal_5fc63986ec20c.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://12350a4d-732a-4148-85a7-4fa27f2a77ec.filesusr.com/ugd/17beed_5706f7d5ac3947a58ce9578b67a096f7.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc79b93a-3339-4f0c-85ae-2dc9dd15c833/g_shock_casio_wr20bar_mud_resist.pdfIn PDF document text
    • https://cd70d4e5-4a1a-4071-96d1-f2415ea5ece1.filesusr.com/ugd/7f46b5_be25de132c894c6da0046097aace1e68.pdf?index=trueIn PDF document text
    • https://13fad4bf-7224-44b3-802b-16842e97d241.filesusr.com/ugd/b14664_7fa0f86da98f439b95e1290c11a1b12d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/644fdcf7-81ae-4c82-8fe2-48676f0c61a3/how_to_fail_at_almost_everything_and_still_win_big_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9d2d2541-292e-424b-bd4f-a191e64a11d4/75619970524.pdfIn PDF document text
    • https://0dd0cd87-80d3-4eb5-b9c6-73c43c3a6fca.filesusr.com/ugd/f0b6b3_1e4fbf6b41c8467ba9dcb3433e3d9a9c.pdf?index=trueIn PDF document text
    • https://a519209a-2b0a-481f-9fe9-460c873bdc80.filesusr.com/ugd/270e53_d672af274d6d4704897eb4f98f993fac.pdf?index=trueIn PDF document text
    • https://4db61c00-1078-4917-8a1c-a2c1480eb6e0.filesusr.com/ugd/c94206_43b6b9e509e94029aec4f3f3c5ff6cef.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_off000106b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B5 5432 bytes
SHA-256: ec458e1d1f1c6f29f304c956e11a9bc0b40473fc4afd560160cb49592833567b
font_01_sfnt_off00011919.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11919 11596 bytes
SHA-256: f1dd0777572a5450b01fa6030fadb89c1027f7c5471ea543a9d48b235eb51765