Malicious PDF — malware analysis report

Static analysis result for SHA-256 28ca3c6c65dc574c…

MALICIOUS

PDF

102.0 KB Created: 2021-08-06 04:57:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f695b3ac2d69d1786ffe5c6ece5bcdf9 SHA-1: 444be4ee2f4a8a8e18f070eeafae88ae8676381b SHA-256: 28ca3c6c65dc574cf9928ab39b1a723f34e937c666fc2053c3567a7b6caa3ed9
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The presence of these links and the overall structure suggest an attempt to lure victims to malicious sites for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://sweetburden.com/upload/users/files/vexigefugikap.pdf In PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160718980d9b39---59827993850.pdfIn PDF document text
    • https://abeess.com/userfiles/file/pumigin.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/cqc85r4d0uhsvv96u0fqm7kh8r/sitawekugowo.pdfIn PDF document text
    • http://baaningdoi.com/file_media/file_image/file/mevufinakedopegifevup.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb84f9b4b8a---50884876674.pdfIn PDF document text
    • https://fonixkoncert.hu/upload/file/nadesokowef.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f4341910ad9---91395706894.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/srlkrl7s1tffjth5liidurin53/bedar.pdfIn PDF document text
    • http://giovanniseneca.eu/userfiles/files/gobasavivam.pdfIn PDF document text
    • http://emurus.jp/userfiles/file/50960337566.pdfIn PDF document text
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/n0ldgsmd3rksqt5tbio8k6hbbg/36966697590.pdfIn PDF document text
    • http://www.lugashotel.com/data/editorfile/57202304532.pdfIn PDF document text
    • http://mmbc.cz/_data/user_files/file/55926858611.pdfIn PDF document text
    • https://sieuthigo.vn/upload/ck/files/70982325650.pdfIn PDF document text
    • http://aaexpansionjoint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097d5a667f38---pojufarejufunenewovuxure.pdfIn PDF document text
    • https://www.ideaklinikizmir.com/wp-content/plugins/formcraft/file-upload/server/content/files/160702d5e0ce5b---jakopuwow.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/dukev.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/16075c5bb430e3---gemaf.pdfIn PDF document text
    • http://rideco.hu/upload/file/taxulo.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/bb4p04sgg69sjmie49t3ieilbf/1338391854.pdfIn PDF document text
    • http://geodeslaboratori.eu/userfiles/files/pelafitarizaxodo.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/47394053923.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=friedrich+hayek+the+road+to+serfdom+pdfPDF 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_off00012c01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C01 10920 bytes
SHA-256: d67a6f76c0522bf3b97f06fb13d6aebc98477d1e094bbb2f61578149e95443b0
font_01_sfnt_off0001455a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1455A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015d6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D6C 17100 bytes
SHA-256: b0a0f72e03b808d9f37a4e2dcc1291cca11969783ab4391e7b07f67535c8fe98