Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8d2254ea5d60fee…

MALICIOUS

PDF

73.3 KB Created: 2021-08-16 23:18:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 34a1e65bc19d976ec7173c746404d644 SHA-1: fad954019bf28bf79ac7ffdd07cdd58d00ce1aef SHA-256: c8d2254ea5d60fee9786d647fd790a2ed579ef7e0cef36139ae6930571576526
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm or SEO poisoning tactic. The ML classifier strongly indicates maliciousness. While no scripts were explicitly extracted, the presence of numerous external links and the PDF structure itself are indicative of attempts to redirect users to malicious content, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

Heuristics 5

  • 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://nomylo.ru/uplcv?utm_term=comparing+fractions+on+a+number+line+worksheet+4th+grade
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/42ad4f5eecfcb58bbcb3b6e808b6739a/repoxebenulanafopenir.pdf
    • http://marcth.pl/media/fck/file/54943748648.pdf
    • http://www.toptehnik.si/images/55700332071.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160f77db7f0628---lakedaxoputog.pdf
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/a7d447b4065872b84155ac7f386e6e0d/rirodawawoxojidepemeba.pdf
    • http://cukiernia-waltar.pl/qcms/userfiles/file/52207425452.pdf
    • http://kaztelcom.kz/ckfinder/userfiles/files/48978546201.pdf
    • http://bandenplaats.nl/cmsimages/file/91707278916.pdf
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/dcf8743bead2f29c888c96790ca80a9a/japukuluki.pdf
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082085eb3c5d---wovazibujenaviwimi.pdf
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a7159f20a2d---kegurepafetusoronar.pdf
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093b8774608e---21900319597.pdf
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d7be97712bd---15847820222.pdf
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/e1dbc8135b2285bfa4d837685e83d8fd/sitaravibajelidilif.pdf
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b00e7a94be---13750741092.pdf
    • http://hitecds.com/userfiles/file/36603299649.pdf
    • http://botosani.ro/img/uploads/file/sirebonilawomedu.pdf
    • http://karpatskiles.ru/store/files/16710289162.pdf
    • http://yishiweb.com/upfiles/files/20210813_114705.pdf
    • https://bselink.com/userfiles/file/36664319630.pdf
    • http://lifemartrealestateconnect.com/wp-content/plugins/super-forms/uploads/php/files/kf5ndqn3jtpsm0u2ni6km81jo7/87594700808.pdf
    • http://colescastle.com/clients/875019/File/redofosubok.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aed7429f02c---susogazaloxetibolaw.pdf
    • http://winhazel.com/indigo/ckfinder/userfiles/files/29703926270.pdf
    • 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_off0000bc47.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC47 16792 bytes
font_01_sfnt_off0000d45e.bin
4d4884edc73de6cf8d9f95c764941e65bf4251d8ec60f27821912a354293b213
pdf-font-stream PDF embedded font (sfnt) at offset 0xD45E 11596 bytes
font_02_sfnt_off0000ef68.bin
7f23701dafb453c01843fa925932820a40209db33a2b9bfb35b42179e0edb2a4
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF68 15204 bytes