Malicious PDF — malware analysis report

Static analysis result for SHA-256 965ed9e8beade571…

MALICIOUS

PDF

81.4 KB Created: 2021-08-27 07:36:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7194465ddd903d2532af3581806e1758 SHA-1: 61ba9b74bc8fe5c6dc36e225155554489814ae5c SHA-256: 965ed9e8beade571d80ae6e9d3949a98b467d10c8f312f4bc1574d03acc5d0db
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of maliciousness. It functions as a link farm, with numerous embedded URLs pointing to various websites, some of which are hosted on compromised CMS platforms. The presence of these links suggests an intent to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://fszhenjia.com/upfolder/e/files/20210528135326.pdf
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/1ba1ae9bdd2325fd2c0a9fbc606d4a72/loketujosajewiwajilawoza.pdf
    • https://an-professional.ru/img/files/file/95109804615.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/de7b6e3625c41750f5871085c52694fb/36995682493.pdf
    • https://webshopplus.nl/app/webroot/files/userfiles/files/vegelobusivupif.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160ae7fb1680d3---14817472414.pdf
    • http://ranahytta.com/ckfinder/userfiles/files/98280134401.pdf
    • http://andrelandberg.com/userfiles/file/35866536390.pdf
    • https://rhagro.com.mx/wp-content/plugins/super-forms/uploads/php/files/af94ef6c9efc845937113f4609d9b4ba/xuwepejiremenuvulujofiwo.pdf
    • http://winterwonderlandzundert.nl/uploadimages/files/5929358194.pdf
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/14762110783.pdf
    • https://gkscam.com/userfiles/file/57068598309.pdf
    • http://www.ecvbrass.ch/user/web/file/zonebam.pdf
    • http://berbun.com/user_img/file/figuvukorudu.pdf
    • https://digireg.pl/upload/31995128661.pdf
    • http://brnc85.com/clients/878796/File/31028712713.pdf
    • http://tubietelbar.hu/uploadfile/55873163774.pdf
    • http://flightshop.jp/images/blog//file/nilirid.pdf
    • https://zevkotodoseme.com/upload/ckfinder/files/jogibawefavumonutoximore.pdf
    • https://victory-agency.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089d7b32abb3---63235143478.pdf
    • https://www.hamburgeriaagricola.com/wp-content/plugins/super-forms/uploads/php/files/oe21rv8vj3ki2mvjnonssjgdg5/sejud.pdf
    • http://hindel-relax.ch/ckfinder/userfiles/files/jobaxopotod.pdf
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16094de1524f8d---75338562153.pdf
    • http://envisystem.com/upload/userfile/files/terivenuxopig.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=happy+birthday+to+you+baby
    • 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_off0000df94.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF94 16792 bytes
font_01_sfnt_off0000f7ab.bin
11045242589ad5d3a8e5edadc4f7b66700f9658b69b7387bd67012ad4f99c424
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7AB 10384 bytes
font_02_sfnt_off00010f02.bin
3697606700dc08b2d77b504a45a347da694855c1dbc8e6fc021c84766c500f47
pdf-font-stream PDF embedded font (sfnt) at offset 0x10F02 15744 bytes