Malicious PDF — malware analysis report

Static analysis result for SHA-256 4958252d62f9eab4…

MALICIOUS

PDF

89.0 KB Created: 2021-06-20 03:11:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 4e123735c494de6b22fbea9f6c9b72db SHA-1: ba8c16726d6d7931eb1792663b9c2f9713243882 SHA-256: 4958252d62f9eab48f2683f22ab43eb323d581483ca2147f43730a028597e784
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to WordPress sites with formcraft plugin uploads, indicating a link farm designed to host or redirect to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple external URIs and a link farm heuristic confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c3711e253---bimat.pdf In PDF document text
    • http://jp-photo.cz/soubory/files/9197333273.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe7b09f952---71583573749.pdfIn PDF document text
    • https://roweryelectra.eu/app/webroot/uploads/file/1620289641294.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a992d30535b---96229861875.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607f065331e60---38355636131.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/lazanirofan.pdfIn PDF document text
    • https://homini.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16073cc4b1cdd7---lidub.pdfIn PDF document text
    • https://www.makathastaliklari.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607a025e4c154---jegejomejegal.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/88a82162ef67e949af9c25a4458ad150/winexerebobasarejesoku.pdfIn PDF document text
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607faec2c605f---77770571419.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ce6d8954fea---pomupojajuripomajopobeful.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090f21dc01e7---rulibaziwagomezirided.pdfIn PDF document text
    • http://polipadel.com/userfiles/file/xaparolosodok.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607c88a5477d1---24214669474.pdfIn PDF document text
    • http://cuuhoatudong.com/upload/files/xolavoxon.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/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=farm+frenzy+3+ice+domain+freePDF 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_004_off000121ef.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x121EF 30008 bytes
SHA-256: d3e1a465aeecbae1c9f141c51c48099872794d921af99e1243299edc86cd9ebb
font_00_sfnt_off0000eaa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA9 5228 bytes
SHA-256: e8293e541c53a384ff8beaaf6239e901a843db39966a4338ff55bbdf45dab692
font_01_sfnt_off0000fc72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC72 10872 bytes
SHA-256: 8b65ed970339d31395c06bd5096db125e8adf80dd3653310fe39d9af6e54e79d