Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a15b7904e0592f4…

MALICIOUS

PDF

75.2 KB Created: 2021-09-27 00:10:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 93f0d3f9596695de2dd1d92185be2911 SHA-1: 46252c4441004193ddde189ea77910564dc9ef45 SHA-256: 8a15b7904e0592f456b0e8b07a10845844bd8ddb9264a52f691c5283eea854e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that form a link farm, a common tactic for phishing or distributing malware. Heuristics indicate these links point to disposable hosting and compromised CMS uploads, suggesting a malicious intent to obscure the final destination. While no scripts were directly extracted, the PDF structure and link farm behavior strongly suggest it's part of a phishing campaign, likely initiated via spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://kietminhrivet.com/upload/files/bijixikifo.pdf In PDF document text
    • http://gaudi.tw/upload/files/11862737816.pdfIn PDF document text
    • http://alumcity.ru/userfiles/file/pobunewujenogag.pdfIn PDF document text
    • http://jodhpurheritagewalk.com/images/file/jujiduge.pdfIn PDF document text
    • http://summitremodelinginc.com/userfiles/files/22440997652.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/kemugusovarapodi.pdfIn PDF document text
    • http://swaminarayangm.org/userfiles/file/dujetitanevexali.pdfIn PDF document text
    • http://gazdalkodjokosan.hu/img/userfiles/file/wiwokoxulafamegarat.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/73636843101.pdfIn PDF document text
    • https://gilbertems.com/videos/file/rulabelewatepedo.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161406fc195f31---gojijekigakuva.pdfIn PDF document text
    • https://popa.com.br/wp-content/plugins/super-forms/uploads/php/files/4d281233c4167a76ea694fdac49fbd33/sinaxudukubi.pdfIn PDF document text
    • https://stauber.lt/images/files/pilezu.pdfIn PDF document text
    • http://investgeorgia.ge/userfiles/file/24778329553.pdfIn PDF document text
    • http://topup-fight.com/ckfinder/userfiles/files/4382154517.pdfIn PDF document text
    • http://uktohabbarijamalta.com/files/file/bavekepipiferi.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/45522870354.pdfIn PDF document text
    • https://coonvalleycc.com/userfiles/file/vidoxisaw.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136cce6bb663---94530873021.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/misukep.pdfIn PDF document text
    • http://tmkb.org.tr/ckfinder/userfiles/files/foriginumamukazofivebabi.pdfIn PDF document text
    • https://signos.larrialdiak.es/files/galeria/files/losofoxolupex.pdfIn PDF document text
    • https://kettosallampolgarsag.net/imagini_ws/15435987310.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=read+happily+ever+after+kiera+cass+online+freePDF link annotation
    • 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_off0000b9a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1BD 11036 bytes
SHA-256: 71e53674b4ffbda9ede12497d84c79ac0a7e2ecd736047c11ee01ba69911ffd6
font_02_sfnt_off0000eb5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB5E 19316 bytes
SHA-256: 251cc9c7cb1ad5c8280dc24433a5aa8d1988b7a3353fd58da81c3ccf34336510