Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a1d3dc25a5a33d8…

MALICIOUS

PDF

91.8 KB Created: 2021-07-07 06:44:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 39c34c29323e1a8274fcb1b5470c95e9 SHA-1: fbae4c8840c06e5067e98b8de2fd1a90ad896dd0 SHA-256: 4a1d3dc25a5a33d88e060ca89e0b170a2d0c758f1b86bb3d33d8d8012ecd1d04
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to compromised WordPress sites and disposable hosting, suggesting an attempt to redirect users to malicious content or for SEO manipulation. No scripts were extracted, but the presence of numerous external links is the primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607743a251633---29621462230.pdf In PDF document text
    • http://massimobertoarchitetto.com/userfiles/files/mejagabepemojazur.pdfIn PDF document text
    • https://lexcochoralsoc.org/demo/lccs/beta/userfiles/files/dibogamabapubojeliwos.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/mosakagilizez.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/suxetodesugarejaximeg.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae210dec722---88276116385.pdfIn PDF document text
    • https://beautyreviveshop.com/newerac2c/userfiles/file/45055708803.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a441fa09d40---6490668149.pdfIn PDF document text
    • https://www.lumisolar.pe/wp-content/plugins/formcraft/file-upload/server/content/files/1608e951eed3bd---3389365864.pdfIn PDF document text
    • http://cnokorea.com/userfiles/file/59747822963.pdfIn PDF document text
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/h9omg02kiqb5p9mj5rd7jufkar/13462770495.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe2680b825---37246026414.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/uadmgehtmkcdeeae7tvgiqu1ib/6798560100.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607c470845520---vusonutaje.pdfIn PDF document text
    • http://gotoippc.com/ckfinder/userfiles/files/monetusosukaxozomapelura.pdfIn PDF document text
    • http://ahchala.com/img/file/jelajirojuvikurowirute.pdfIn PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/639c19205faedece662257fd2ee3a940/jatexo.pdfIn PDF document text
    • https://www.ccps.mx/wp-content/plugins/super-forms/uploads/php/files/7f6d48c7dc1ed3b28d3831ba3a1e7a7e/38430597030.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/cafd95eedd11d20f956c841437e423f3/vixapivefezi.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/d1c8f2a689414909ec1f50a8deca8fa9/49301605591.pdfIn PDF document text
    • http://grani-tonkogo-mira.ru/wp-content/plugins/super-forms/uploads/php/files/a94fa05c6e562e5c91838d653948f9c5/bekekigavo.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a098a4a1afa---72349252895.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/509692c5578c5c9fa7a7d6cb8bcba255/tosozeme.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=witcher+3+does+romancing+shani+affect+yenPDF link annotation
    • http://lovewhereyoulv.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/2dc60d585682aa0d20dc09a7f8a19b97/25926434985.pdfIn PDF document text
    • 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_off0001023e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023E 17444 bytes
SHA-256: aa1432d1fe9ddb796f5219c4dc771ca1571644040ee36fb18da93f2537109386
font_01_sfnt_off00013009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13009 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14820 11156 bytes
SHA-256: be9818296d0a93e908d134ddfa01327549675fbe8663dd259469d621eaa7dbaf