Malicious PDF — malware analysis report

Static analysis result for SHA-256 37df48f148a8e8a7…

MALICIOUS

PDF

93.7 KB Created: 2021-06-30 23:09:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6e40f8b608829cc203b718ffebb1b3ea SHA-1: 771c5dcb668b3705a120b1d43927e9c93e4f36fe SHA-256: 37df48f148a8e8a75243b37323db0697bbe2f53de92b3420b19589f50c9c5b72
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The PDF structure itself is also noted as having duplicate object bodies, which can be used for obfuscation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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.
  • 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://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16079dc13e6f0f---79995933692.pdf
    • http://yaeram.com/userData/board/file/kuduxexalo.pdf
    • https://kvkumariajnkvv.org/singhania/downloads/file/nojifadigoke.pdf
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080223145354---xitusorilawonovufojawap.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609dcab041d51---28091506894.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/160813c7793322---duxigemojoledobera.pdf
    • http://www.siscard.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc60698a9a---sizujuxev.pdf
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ee45f36572---vadazo.pdf
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/psqufos5pth0lqo29brerhgmcm/12763232028.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f06f4868d3---wadonegemidoradum.pdf
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082bd855df4d---farapapobokodenut.pdf
    • http://dnepropress.net/files/file/64885692369.pdf
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b545deca0e7---25851261644.pdf
    • http://www.festivalmarrakech.info/wp-content/plugins/formcraft/file-upload/server/content/files/160acb1edde1e7---niwaredopidozukunolifew.pdf
    • http://rajskiewakacje.pl/userfiles/file/xirejam.pdf
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/5kdv6fd5ssg3mh1n3ni68clu1o/52720817818.pdf
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1609b5355c2d7d---17935163758.pdf
    • http://akwarella.pl/user_uploads/file/tedolawanilawo.pdf
    • http://auxerretv.com/content/public/file/78154503156.pdf
    • http://kcde.kr/userfiles/file/6248713680.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/329fc4c37d6f40822829e127718eb42a/nexosijozo.pdf
    • http://pahsclassof2005.com/clients/d/d6/d61c4c031b0f3af13d3e88110ef3a3e1/File/bovoxuduxabaniwepoxama.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=local+knitting+stores
    • 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_off00010d33.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D33 16792 bytes
font_01_sfnt_off0001254a.bin
4d8986748f0e22217986253e1b7aae5c92b243d89cac5187b972e6baf83c50a0
pdf-font-stream PDF embedded font (sfnt) at offset 0x1254A 10452 bytes
font_02_sfnt_off00013d26.bin
0c45de878dd0992dfc766330a0a16fa0d98cbd5f6465641d168377112600c6ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x13D26 16612 bytes