Malicious PDF — malware analysis report

Static analysis result for SHA-256 840f91b289db5bfc…

MALICIOUS

PDF

85.4 KB Created: 2021-07-13 21:47:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cd4f128eb25c4583082dc6b14eb11a7c SHA-1: d52687fe7149c03b78704dcd426b7ed9cab9b4f0 SHA-256: 840f91b289db5bfc6a558fa063afc03c48754de0fcd81e41af1705542dade73e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links pointing to compromised websites, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/6ea4ada0d338661d225604c7d555b86a/85397540927.pdf
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608dce15ec20d---jegilemixobutatasudu.pdf
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/43978191754.pdf
    • http://ciaooo.ru/uploades/userfiles/file/roxegizizetekekudapixuwir.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/2emmrf29shm9qjhoqont4keo3j/81716603947.pdf
    • http://ozdoby-betonowe21.pl/Upload/file/42677973380.pdf
    • https://advicezone.org.uk/wp-content/plugins/super-forms/uploads/php/files/1ka134udelnb1556929lh9ecim/misexavotigiko.pdf
    • http://waltwhitmanhsclassof1970.com/clients/3/38/385e9ad2c098ba3bcab8db81b262ab1e/File/fugapesomaw.pdf
    • https://alate.org/admin/fckeditor/editorfile/98518590228.pdf
    • http://softwarefactory.nl/images/file/zobamojijonutabodisiki.pdf
    • http://sip7.online/wp-content/plugins/super-forms/uploads/php/files/db8d444a2fe29a5b00146cb7e2997767/45256390221.pdf
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d7e91b7d7---pamefujeve.pdf
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/092b775310ffe4422f1718a4252a9471/fonaronivodidanetora.pdf
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/per7s56mkku811hioei2ofr869/8196269775.pdf
    • http://dianacb.cz/userfiles/file/sazivezevaze.pdf
    • http://thaoduocquyhiem.com/userfiles/image/file/54744369670.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1b542b4645---dedevaxubuxudowaj.pdf
    • http://lamekatus.ee/uploads/ckeditor/files/81042352699.pdf
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/tcfe5vgqh3mfgu9b4fpiblgl4d/puzumogujoxibewibi.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c14ff93ad4---fudosepisepufafarekav.pdf
    • https://zoldlepes.hu/userfiles/file/deruwoluwifawufanadutu.pdf
    • http://movitecnic.fr/ressource/site-image/files/74740850194.pdf
    • https://newtech-utm.pl/userfiles/file/67787792288.pdf
    • https://daismene.it/file/5133611624.pdf
    • https://landlorddebtadvisory.com/wp-content/plugins/super-forms/uploads/php/files/87ktknd0ckjqr0gscvlaclkvu3/bugasu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=booking+online+license
    • 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_off0000ee6a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEE6A 16792 bytes
font_01_sfnt_off0001067c.bin
0344e0c5a5c7f2110d114f6a223a147b3a7684c1f05b3c64c9345f7eead56b21
pdf-font-stream PDF embedded font (sfnt) at offset 0x1067C 16568 bytes
font_02_sfnt_off0001319f.bin
ba8fa7b620e8148f4df5e6304460cd2f68a6511f6e1c9c610564c273f2884ddf
pdf-font-stream PDF embedded font (sfnt) at offset 0x1319F 10192 bytes