Malicious PDF — malware analysis report

Static analysis result for SHA-256 558544c76bac8361…

MALICIOUS

PDF

86.8 KB Created: 2021-07-05 14:25:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 14fe1bef7cc0568a1f5ea0214bf97305 SHA-1: 92343b17af579dec611076da5843889a1e52dfde SHA-256: 558544c76bac83615e8a8928b51b3b55341b6f884fb652ab2afd2ec2680d5865
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous external URIs, many pointing to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The presence of external links and the nature of the heuristics indicate a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://crysiq.ru/uplcv?utm_term=doxycycline+before+bed
    • https://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/481b852b84d8c8408385e03ce0864978/83103436502.pdf
    • https://questyme.ca/userfiles/file/79352220095.pdf
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/c5815t73arcoje71aq4p0s7ov3/39491274655.pdf
    • http://cunningham-reunion.com/clients/7/73/7399477c88ef979e1ad3ac38e42cffcc/File/revoxobijosevijesixilemom.pdf
    • http://lmleadmanagement.com/userfiles/files/55045689180.pdf
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/dff1f3c9bf214f5f5c64a3bfaac5b5e1/80004371310.pdf
    • http://www.argentum.com/wp-content/plugins/super-forms/uploads/php/files/efuo5pkfl4r8la7lo7n0p7c72u/34213725664.pdf
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a2b9b43edb4---8548207355.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/16078def996f15---28351546009.pdf
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb6ca3f0b8---wodez.pdf
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/950d826e68856502debc6f80e8d7fb4b/nisibatokarelolulopuba.pdf
    • http://asupuro.com/user_data/image//file/66116399541.pdf
    • http://kamnitikamini.si/upload/files/35851627558.pdf
    • http://livestreaming.group/wp-content/plugins/super-forms/uploads/php/files/bgh7aldsub988cuifjl2jftts0daldkj/65047279055.pdf
    • https://ivaco.it/file/87883579847.pdf
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/62d25616e1e59934eee68947a4eaeb05/sawap.pdf
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/0c51383d107b61cf773b90122d8840f6/vutupugavin.pdf
    • https://samoinstitute.mn/uploads/assets/file/51665989884.pdf
    • https://www.elektrobetrieb-scholz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606c859f9ea7b---19901200857.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c98b30b9dc5---13833628273.pdf
    • http://gerocuki.hu/user/file/45821981160.pdf
    • http://ip-golubev.ru/ckfinder/userfiles/files/65335185263.pdf
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a079c2b6358---gerem.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f118.bin
415974eb6d9afca82586a21c701e2ba6e0921ba2fb6b540b87e5d185d9fdbd24
pdf-font-stream PDF embedded font (sfnt) at offset 0xF118 17284 bytes
font_01_sfnt_off00011e4f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E4F 16792 bytes
font_02_sfnt_off00013666.bin
ceccca803afd56f21097c482d4933a4ba96d8f129c575f26b19b050223f14ed6
pdf-font-stream PDF embedded font (sfnt) at offset 0x13666 10396 bytes