Malicious PDF — malware analysis report

Static analysis result for SHA-256 8632671e7d193264…

MALICIOUS

PDF

83.8 KB Created: 2021-09-05 16:31:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 4991c4405206c5dfb04c25c5181f3fe7 SHA-1: 35d2c5cc3a25a4b9335800dd34e643e91d245fd7 SHA-256: 8632671e7d19326499491cbc7441a5dd6e64b8458ce9c0f9bfb0fbb9a6fa92b5
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites acting as a link farm. These links likely serve to obscure the final destination, which is another PDF file. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/riekeam26rhjmdn9equd8njjfr/12412203047.pdf In PDF document text
    • https://wedding-photos.cz/userfiles/file/5804863959.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/wuwiroboxatodogetapada.pdfIn PDF document text
    • https://fa-vietnam.com/webroot/img/files/69542059414.pdfIn PDF document text
    • https://beaszemin.com/files/11601075931.pdfIn PDF document text
    • http://pusheng168.com/uploadfiles/20210809193800.pdfIn PDF document text
    • http://bsl-trans.ru/admin/ckfinder/userfiles/files/39414392739.pdfIn PDF document text
    • http://cioccolatogallucci.it/userfiles/file/mubujumidofed.pdfIn PDF document text
    • https://netshopnepal.com/userfiles/file/26731162253.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/55a682642687bb3282ddfdc69e639f14/62883667547.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160711596eb00e---bukapakikisidur.pdfIn PDF document text
    • http://tai-yang.tw/taiyang/upload/file/nedafebez.pdfIn PDF document text
    • http://kag.fr/userfiles/file/vugapenomunugulepurigazus.pdfIn PDF document text
    • https://olmitek.by/wp-content/plugins/super-forms/uploads/php/files/j4socbomgequm0pdd714un74k2/viniweberesodikirut.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/4348ed8941ea3fd52809a975644c1636/79778613887.pdfIn PDF document text
    • https://praktijk.zorglink.nl/ckfinder/userfiles/files/31637696627.pdfIn PDF document text
    • http://avtoarka.ru/wp-content/plugins/super-forms/uploads/php/files/39f16f16be1b62f7f3664ba760346902/9717867414.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b62da3e48fe---5654875178.pdfIn PDF document text
    • http://aqcons.vn/upload/files/vamew.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/16086ff2775c11---fanovube.pdfIn PDF document text
    • http://womensmentalhealthmd.com/clients/9/9a/9a9ccad1be43d50cbc9928f06550b956/File/wavunezomozeda.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160a93b5ec3136---98157219751.pdfIn PDF document text
    • http://www.cerathai.com/image/upload/File/fasulaleriwapoposigibosaz.pdfIn PDF document text
    • http://theemasternetworker.com/ckfinder/userfiles/files/zewupixorosenaragerusibu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=cazadores+de+sombras+los+origenes+2+pdf+google+drivePDF 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_off0000dc44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC44 11160 bytes
SHA-256: a3523ff1a6bf3bda5edd6b98eccd898f68937a24d9d3d5eea15177335a82186b
font_01_sfnt_off0000f5f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F7 19392 bytes
SHA-256: 4aa51052117a16b2791c8cc14999311d4251832527473351b5cb963455de703c
font_02_sfnt_off00012724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12724 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1