Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb1857b56a233cc1…

MALICIOUS

PDF

68.5 KB Created: 2021-09-26 16:56:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b4f96270878dde755abb2810c1af7293 SHA-1: 104d13b7a3e8c141553ffee239c3a855cd38399e SHA-256: bb1857b56a233cc126482fe85da36baf44ca2e4f82b8a03de3ae1fa1f73f7d27
116 Risk Score

Malware Insights

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

The PDF is identified as an image-only lure, typical of phishing campaigns. It contains a large number of embedded URLs pointing to various compromised websites, suggesting a link farm designed to distribute malicious content or redirect users to phishing pages. The ML classifier strongly supports the malicious nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 1 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://chcial.ru/uplcv?utm_term=cleo+scripts+for+gta+vc+android PDF link annotation
    • http://csc-0411.com/userfiles/file/20210919215421_2h79ks.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/9a9a2500000825f155e1736555cf515f/wunodusivasovurabotijinik.pdfIn PDF document text
    • http://www.badischer-kunstverein.de/ckfinder/userfiles/files/81016244610.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149b28e62e3c---52569647941.pdfIn PDF document text
    • https://chiataiec.com/userfiles/Proj_Name/files/77253229433.pdfIn PDF document text
    • https://panelshock.com/userfiles/file/vefetikirej.pdfIn PDF document text
    • https://rainbowprinter.com/app/webroot/files/file/zapajazusixaluged.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/kbl8hj3v05ddpej89o0hvjbm6t/vivuluxax.pdfIn PDF document text
    • https://nceptionsolutions.com/wp-content/plugins/super-forms/uploads/php/files/067ff333c2a513a0a277dc925a2579d5/tevitirulomuwa.pdfIn PDF document text
    • https://esterkins.de/ckfinder/userfiles/files/nebujaribek.pdfIn PDF document text
    • http://nhakhoauytinhaiphong.com/upload/files/tukar.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/90576314161.pdfIn PDF document text
    • http://sunnyten.net/userData/board/file/xanabofik.pdfIn PDF document text
    • http://www.florentmaussion.net/userfiles/File/femodobugowerivit.pdfIn PDF document text
    • https://akvanova.ru/sites/default/files/9487459490.pdfIn PDF document text
    • https://www.delaneyllc.com/ckfinder/userfiles/files/bibinonejaravafedo.pdfIn PDF document text
    • http://oresteruggiero.com/userfiles/files/zowumosamupolizadukutaz.pdfIn PDF document text
    • http://steinemann-ag.ru/tugut.pdfIn PDF document text
    • https://scout-educationguide.com/userfiles/file/80127769792.pdfIn PDF document text
    • http://ellev.fr/upload/files/silaketagifix.pdfIn PDF document text
    • https://rajatotogroup3.com/contents/files/kaxosatog.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614139a553d53---29673755414.pdfIn PDF document text
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/vawiroge.pdfIn PDF document text
    • https://oferta.lt/i/File/rewufepo.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_off0000af6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF6F 14428 bytes
SHA-256: 87ab7afff9a42b717e0740b1cd07b65933f6a5c3b071d0de7d07eaaef51cbf00
font_01_sfnt_off0000d371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD371 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eb88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB88 10892 bytes
SHA-256: f97439ba4920dfc45c4fe1f0425522b88cd23349389cfb22ba2622b54649446d