Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9a1bf821568bb8f…

MALICIOUS

PDF

80.8 KB Created: 2021-07-18 23:34:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 162e7e95f2a8867b07d87e02827083b9 SHA-1: ad646cfff6afa40af6d11fd9b55146f63644d455 SHA-256: a9a1bf821568bb8f90e33624e71e9fb0389c098b47fa1d22fba9785cd5cb1267
156 Risk Score

Malware Insights

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

The PDF contains a large number of links pointing to various websites, many of which appear to be compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of numerous external links suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://xigmatek.com/upload/files/1662837768.pdf In PDF document text
    • http://yuanjen.com/ckfinder/userfiles/files/welipinazaluj.pdfIn PDF document text
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608bf4b24e927---xuvubimafidap.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/9f3d264d2589e08d85d5b74ef447dd4e/23883014821.pdfIn PDF document text
    • https://www.hauptsache.cc/wp-content/plugins/formcraft/file-upload/server/content/files/16081dcf4c7d10---dujipedojir.pdfIn PDF document text
    • http://tuhs1970.com/clients/a/ac/acc339db084e87cdfae31a76a6c96f1c/File/85391431055.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609943d5468b4---subowexer.pdfIn PDF document text
    • http://zuestag.ch/userfiles/files/79926341071.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f85405577a---salijade.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/5d9101026332fe3dfab69118acc87a33/sepurikapudorituruval.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c558b5dd9ea---tukiwalomulunovebagi.pdfIn PDF document text
    • https://www.adelaarenergy.com/wp-content/plugins/super-forms/uploads/php/files/hf30bmsoe1cqcruogca06jul7b/kuvat.pdfIn PDF document text
    • https://islandsvefir.is/wp-content/plugins/super-forms/uploads/php/files/0s40u38gsk9rhl0vv28a1ouhqu/xaliduvadejeluko.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085c25c42334---nunugibemefunevoboru.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/navuvagifiwapunidem.pdfIn PDF document text
    • http://byty-pardubice.eu/UserFiles/File/putipekudaz.pdfIn PDF document text
    • http://chapmanhighschoolclassof1968.com/clients/c/cb/cb1fed5110c07f199f416a264ee6943c/File/43782824747.pdfIn PDF document text
    • http://harryreichert.de/uploaded_pics/News/file/69659877683.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608442f283b18---62448852184.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/428dd480714bd11ee94fa6094090448a/kixiwofo.pdfIn PDF document text
    • http://whatdwellswithin.com/file/jujusejuvoserudufajasuba.pdfIn PDF document text
    • http://marinapogon.pl/upload/file/72697477316.pdfIn PDF document text
    • http://majorpropertygroup.com/userfiles/files/54652193101.pdfIn PDF document text
    • https://vestol.bg/files/file/4688544376.pdfIn PDF document text
    • https://avantkart.com/wp-content/plugins/super-forms/uploads/php/files/8078a9p8lbc361fd3ke1pephv5/xutuname.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/65549152957.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=amber+brown+is+not+a+crayon+read+onlinePDF 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_off0000d680.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD680 18012 bytes
SHA-256: 6f6ee1cc720e58d52b16108f4dc9471084227fde2a32331880d8410a0644dcfd
font_01_sfnt_off00010475.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10475 10852 bytes
SHA-256: 984312cda91e62013865cb357345dd14ac83dbf2bff8b7cd9287c31450a94db6
font_02_sfnt_off00011d9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1