Malicious PDF — malware analysis report

Static analysis result for SHA-256 9eb671796e982261…

MALICIOUS

PDF

91.1 KB Created: 2021-08-19 13:58:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6b7a4dd805c15ebc8775d52c351f3371 SHA-1: 991b1338381eb8f6e253c88ac49a7032688fb85c SHA-256: 9eb671796e982261915636de281bcc3dccf630ba7ca366a67215a8b66b818ec0
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to other PDF files hosted on compromised CMS upload directories. Heuristics indicate this is a link farm designed to obscure the true destination, with a high ML classifier score and ClamAV detection confirming malicious intent. The primary attack pattern involves directing users to potentially malicious content via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16078f75c9face---xumijulowenidetagezalozu.pdf
    • https://atcotourismtravel.com/userfiles/file/5167391174.pdf
    • http://degrossier.nl/uploads/file/12526115689.pdf
    • https://ceral.pl/ceral/pliki/file/vakowon.pdf
    • http://xnucleus.com/members//member_images/files/bakuwefarixutokatojuvag.pdf
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/65e990403ef122ac93cbad56996a19f4/94512791062.pdf
    • http://nhuaduongnhapkhauaz.info/upload/files/gofimifixowoboka.pdf
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160accff79f3d1---zoxan.pdf
    • https://personalloan2u.com/wp-content/plugins/super-forms/uploads/php/files/d1a5ada0755d166cad3daa76472d06d4/mimotitojowevijojamiwalu.pdf
    • http://augsburger-dartliga.de/uploads/file/84947454736.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/j638lqnosv9ocvidma8qi09fl0/zubema.pdf
    • https://etonbio.com/newsLetters/images/file/jonunixuxifepev.pdf
    • http://cjandjunemillerfarm.com/clients/75830/File/werovigep.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160c06813f18ee---jirogixuji.pdf
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160b05e0a03d9f---2716547510.pdf
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b74d8eb7854---30477449687.pdf
    • http://impex-italia.it/userfiles/files/85986126596.pdf
    • http://parentini.it/userfiles/files/87659723618.pdf
    • http://ahcxdq.com/uploads/file/280231342801.pdf
    • https://graffitipaintstudio.com/wp-content/plugins/super-forms/uploads/php/files/b0225bc1579b6695ec66bebe82dae05c/suxutibaluvobifit.pdf
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/24c7af3b52e1e055853eb9c77c4053a9/50489734104.pdf
    • http://anhuishangbiao.com/upload_fck/file/2021-4-29/20210429183552324919.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=long+list+of+square+numbers+up+to+100
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e889.bin
325c5f5cda05429ae92d15c23118ca1b8712e485108c584e1e30b0ff615913b7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE889 16084 bytes
font_01_sfnt_off0000fdb6.bin
c750ad5c089a0429e56f24592cc2e95186fc50625a3210b1632f0b70b3d6f1b2
pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB6 11216 bytes
font_02_sfnt_off0001177e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1177E 16792 bytes
font_03_sfnt_off00012f90.bin
df5fffa89976a279172d3498e27600c5daba9ed075a2ff45029e44def774d116
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F90 17344 bytes