Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5a8f2a0c5528245…

MALICIOUS

PDF

80.9 KB Created: 2021-06-25 14:28:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 3bd226b52508bee1720e09e0a229f7cb SHA-1: 2de2808e110eb34d422c15171caf02995377e2df SHA-256: c5a8f2a0c55282454334572dd80660c169561036db8070f77f47b0ee4f7f3354
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress installations or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the extensive use of external links is the primary attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://smidgel.ru/uplcv?utm_term=english+lessons+for+adults+beginners+pdf PDF link annotation
    • http://www.celso.org/download/29169184704.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608542bedd6a4---93434296381.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a1a1e423684---letupovisubupejazareluw.pdfIn PDF document text
    • https://phase1acoustics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abfded0162c---pedazuzezowizokazek.pdfIn PDF document text
    • https://luminex.pl/upload/file/womudadabijevexiz.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbd922f21e---bopuwuvidigujovugoside.pdfIn PDF document text
    • https://absolut-fit-and-dance.de/wp-content/plugins/super-forms/uploads/php/files/145eekancjj9p17q6r1lotr4am/66347042812.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/7b887914fab3ad45e327896afee1f9db/68586561361.pdfIn PDF document text
    • http://www.itbaloch.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c32000f0ed3---23038781728.pdfIn PDF document text
    • https://noddy.nu/images/file/40884629327.pdfIn PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/6mmg3rlinmtk8frl31kut7jd5f/duleripatoxumaxukow.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/q25u0thvvh100149s4bbejek05/81896494652.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/3a00185cca1ab0e4f9b2bb8adbd08585/wirirogijesaxeluteg.pdfIn PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8ad7b2c1f---fajuxezixuvilafoduri.pdfIn PDF document text
    • http://mai-colle.jp/userfiles/file/19600106989.pdfIn PDF document text
    • http://telegid.tv/userfiles/files/wegevedekefufemeju.pdfIn 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://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_off0000dae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F2 16684 bytes
SHA-256: cbe4e9dda3ba38dde66c6629bab85924d04b9781cc30838e1a6d3ecae7917c6e
font_02_sfnt_off00011dff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DFF 11000 bytes
SHA-256: 8468b4b2358d43c1f2b75ec602c43396f7d3dd78a9e32c4d6c7aa5e4531a08eb