Malicious PDF — malware analysis report

Static analysis result for SHA-256 58e6b83431324544…

MALICIOUS

PDF

74.6 KB Created: 2021-09-05 10:07:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: dcf1b6ad124875cd401aaa6efbc792f7 SHA-1: 6d491e555ee1a800646f61bda3a164afc843a8ba SHA-256: 58e6b83431324544e71336f17d7f83ecf462edb7cf9e2540cb0113e20b2b9fe1
156 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 designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://pistant.ru/uplcv?utm_term=mos+capacitor+nptel+pdf PDF link annotation
    • http://rauvuonsach.com/images/uploads/files/16438308271.pdfIn PDF document text
    • http://zoop-tech.com/ckfinder/userfiles/files/balebepavubitavo.pdfIn PDF document text
    • https://xebecdesign.com/xebec/userfiles/file/68347428711.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/54028402584.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/160be2a0654b42---gutisewutawozemekodarin.pdfIn PDF document text
    • https://ottopianos.nl/files/nirakewus.pdfIn PDF document text
    • http://icbiz.ru/userfiles/file/25404372371.pdfIn PDF document text
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160744ef5e200a---vovopijuxubigunajikefe.pdfIn PDF document text
    • https://familienarbeit3plus.ch/userfiles/files/tutiponarolugoguko.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/73409497817.pdfIn PDF document text
    • http://supair-lux.hu/ckfinder/userfiles/files/11813903844.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f34de9ef7a---32310358115.pdfIn PDF document text
    • https://rosewoodcity.org/nbloom/fckuploads/file/bibegidukixi.pdfIn PDF document text
    • http://giwajib.com/ckfinder/userfiles/files/wigap.pdfIn PDF document text
    • http://absolutelyneon.com/userfiles/file/65950440974.pdfIn PDF document text
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/c8f045062c243070c86fe7c4dd9f21c3/gafasumivujelovi.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/lolowejovamumekezoxolufu.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/16085d340710c3---kobokajedixideketojitiked.pdfIn PDF document text
    • http://zkojicin.cz/userfiles/file/54186966582.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/40344209619.pdfIn PDF document text
    • https://sasalidayanisma.org/uploads/file/velatepoxatigefot.pdfIn PDF document text
    • http://www.solarwindependence.com/ckfinder/userfiles/files/mavug.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_off0000c10a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC10A 10608 bytes
SHA-256: 805782818cf0207fcc609450e007d5bc9e74ac157081c6fe4019ca607a623b4b
font_01_sfnt_off0000d96e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD96E 16752 bytes
SHA-256: 86359e7df8471b7c0ce0c66031b269feffc339e8b375653946ea44b2c866f928
font_02_sfnt_off00010509.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10509 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1