Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fcea97d3b731b67…

MALICIOUS

PDF

76.2 KB Created: 2021-06-20 07:59:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 9cb0c66ec53f7d55927313f9776d19dd SHA-1: f307d827a3dc966ae54214c455c26d9c80ab7ff0 SHA-256: 3fcea97d3b731b67d81e0484c6f1595351204436a3d24f10ff83b7e9d7f85444
164 Risk Score

Malware Insights

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

The PDF contains numerous links to compromised CMS upload storage, indicating a link farm designed to host and distribute malicious files. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to lure users into downloading malware disguised as legitimate files. The presence of a 'download button' heuristic further supports this phishing-like lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160827b31215b9---gefojawusuzeje.pdf In PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a32eb5c085a---fojak.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/51fe3203b3db0b683af0c006056d598c/12631925856.pdfIn PDF document text
    • http://vswet.ru/f/satabajigamitejinoti.pdfIn PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b8424dee273---dimusoletelivevik.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609fcb643633d---pebopov.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607982ef4e64c.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/6023cdf57a01f9ce7fbd0afbd06485cc/fetejugavatite.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/0be7d50e578ed991bf22c3219c97cf95/62902829286.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.fr/userfiles/file/91534644944.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609d318790ad0---vazebisexexet.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160808aa49b746---lusipabexelam.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/d025e5ed0bcbe1ad516c15785e3ad6c5/jiposagegefigulapinonow.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abdce579a91---83334017602.pdfIn PDF document text
    • http://kolaykanal.com/userfiles/files/34880657249.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/46682302466.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=8+ball+pool+mod+apk+cuePDF link annotation
    • 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_off0000eb62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB62 5248 bytes
SHA-256: 51b81dcf2afc3b4e072d83f8c0a620f1a4041b0bbdf198f1dc00a3bebc9a9213
font_01_sfnt_off0000fd26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD26 12528 bytes
SHA-256: 190965970f2a2b36d2343acd148a55b5b4c436aa57227ef9bb525b54ffe71117