Malicious PDF — malware analysis report

Static analysis result for SHA-256 5591c96a0bb335ad…

MALICIOUS

PDF

80.9 KB Created: 2021-07-21 17:54:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 48f2c723ecd9d378159e536cd17964d3 SHA-1: 773b2177d780adfba68c8bd63c71427e22faf9c9 SHA-256: 5591c96a0bb335ad7bec5393c72ddeb04e39e7708a0700f384ee3890e045c44a
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised WordPress sites, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient for this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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://sinara.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607a3bcced038---vifila.pdf In PDF document text
    • http://leilehua76.com/clients/4/4d/4d80c013f15dbe3c797666a457780dca/File/29108211751.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609c07ad852f1---7815251192.pdfIn PDF document text
    • https://www.aserspa.net/wp-content/plugins/super-forms/uploads/php/files/hhoj1srmjqg5fs7odbtri4tjkv/97327894791.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160872823b137d---26920368447.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/982a420bee12d9359550e298364c000f/97884872749.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/lifise.pdfIn PDF document text
    • http://sola-brothers.com/userfiles/file/70292788047.pdfIn PDF document text
    • http://burragebrothers.net/demo/jolie/beta/userfiles/files/rufixepivoxil.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/9baa8uaa58n6bmo8iq2njelq0e/wemajugodabejufipifipitiz.pdfIn PDF document text
    • https://netwindowvn.com/uploads/userfiles/file/puzezimekefofebapepaga.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a271be2d42d---karozapabujewinutiluxugip.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/f5adf61e16d66093fb41edc769d451ae/90845258308.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/73801290621.pdfIn PDF document text
    • http://trungtinjsc.vn/upload/FCK/file/9882999741.pdfIn PDF document text
    • http://www.luminicaambiental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098bf2ad16ed---winuperabaloxogatubikox.pdfIn PDF document text
    • https://www.saammohaseb.ir/wp-content/plugins/super-forms/uploads/php/files/cd1617bab8064d3a56b8bf01ba64c4a5/pozege.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a152b98fd76---radoxexo.pdfIn PDF document text
    • https://shopabrang.com/images/files/kewokerif.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/5bcbacdece4d6f4065dd1e2c2539b851/64606421037.pdfIn PDF document text
    • https://atamergranit.com/userfiles/file/95325284335.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/4agovu83eendvrrrugjoio7lh5/48375724531.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/86182366149.pdfIn PDF document text
    • https://www.properties-thassos.com/wp-content/plugins/super-forms/uploads/php/files/7804q5a1kmsvu3ftidoi7pia00/wulabim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=highest+common+factor+of+60+and+96PDF 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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d63c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD63C 11328 bytes
SHA-256: 611712106909cba64b43893f931dc2da8bf0539ee99fb82b74b546d37ee67a98
font_01_sfnt_off0000f05d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF05D 17100 bytes
SHA-256: 92614e6977de2739d999750c0092b6dbb721f7c8b60c33c028470090f7d0a87d
font_02_sfnt_off00011cce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1