Malicious PDF — malware analysis report

Static analysis result for SHA-256 71adbe8d2389485d…

MALICIOUS

PDF

80.3 KB Created: 2021-09-16 14:36:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 733d5d16be5362ce420bfe7f4f251807 SHA-1: 77718da2162462cc7e06a54eff7ae88170929b57 SHA-256: 71adbe8d2389485d500956e71843c480d2133ab918e100d146c8700c526769d6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and links to compromised WordPress upload storage, suggesting it functions as a link farm or phishing lure. The PDF structure and embedded links point towards an attempt to redirect users to potentially malicious content hosted on compromised or disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://oniceh.ru/uplcv?utm_term=android+how+to+merge+contacts PDF link annotation
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/051soddubm97gh4fejlceku5m7/wamidapizirizogupanu.pdfIn PDF document text
    • http://srihemkuntschoolint.com/slbdavbatala/userfiles/file/vebebexurugivenudojadon.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e568d4332---tomete.pdfIn PDF document text
    • https://sedefartphotography.com/resimler/files/705273341.pdfIn PDF document text
    • http://tencanpowder.com/d/files/fimajalodanuwijadul.pdfIn PDF document text
    • http://paramountswimwear.com/userfiles/files/53150518814.pdfIn PDF document text
    • http://newabel.com/ckfinder/userfiles/files/badizemekazufotavaxovix.pdfIn PDF document text
    • http://qapoll.com/2015/vat/upload/files/77369621066.pdfIn PDF document text
    • http://reyazahmad.bscsaoner.in/ckfinder/userfiles/files/25660214533.pdfIn PDF document text
    • http://kxqcgs.net/filespath/files/20210911012345.pdfIn PDF document text
    • https://proartgaleria.hu/files/files/81242506274.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/a28655bbde05e76e502167dfede1bb8b/53915989842.pdfIn PDF document text
    • https://webaprint.be/img/file/4131927987.pdfIn PDF document text
    • https://whereestar.com/marinarubicon/admin/file/41252878966.pdfIn PDF document text
    • http://studioguatta.it/userfiles/files/57895673224.pdfIn PDF document text
    • http://sino-web.net/filespath/files/20210911063314.pdfIn PDF document text
    • https://aglogistics-bo.net/userfiles/file/tuzafega.pdfIn PDF document text
    • http://jowinbio.com/upload/files/202109161457095295.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/f50d0649d5ccc196d21a4c6e45913aab/javafitivusiruvopo.pdfIn PDF document text
    • http://belniig.by/public/file/72242044901.pdfIn PDF document text
    • https://mjrspot.com/fckimages/file/nosizobupapikirom.pdfIn PDF document text
    • http://sh8ke.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ef25ed6494---55081529135.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_off0000d798.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD798 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFAA 16644 bytes
SHA-256: 1ce514e19525c24bb12d095f3ab528f992308fe39ca8e5664a399142b856d22e
font_02_sfnt_off00011ac5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AC5 10836 bytes
SHA-256: 747df2bd7b7f91c13454bb720c94fb6ddafc71e3cab01fed2ca989e3fbf95918