Malicious PDF — malware analysis report

Static analysis result for SHA-256 99cc580e4ae3ce78…

MALICIOUS

PDF

80.8 KB Created: 2021-09-21 09:19:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 56fa830ce05c41843ba1566b98ef8f25 SHA-1: fc68b94f2b736be06de3047fd8ee5b85d0b278fe SHA-256: 99cc580e4ae3ce787a68a6b2d892914c8da3442ec3ee8e4879d4e1016226f265
156 Risk Score

Malware Insights

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

The PDF contains a link farm, directing users to numerous external URLs, some of which are hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is heavily obfuscated and does not provide further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://mirrorlink.com/public/files/files/zawezaxanaxikuw.pdf In PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/d5b6e603de488461866c32372bce80c9/72480013090.pdfIn PDF document text
    • http://aweibel.com/Photo/file/96048907958.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f6cbdf5822e30c970465e06816c30c51/25841965816.pdfIn PDF document text
    • https://detectagsafety.com/ckfinder/userfiles/files/peruras.pdfIn PDF document text
    • http://guojingmall.com/userfiles/file///ramufiferamojaworaxujivor.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/85317497898.pdfIn PDF document text
    • https://nevisnews.com/userfiles/59029928431.pdfIn PDF document text
    • http://ageddfjtj.pretty-match.com/upload/files/62958477930.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140ed361c1eb---84373452575.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/8c757ed6d3f99ca1dcc1a731a10c39a6/98549740971.pdfIn PDF document text
    • https://vnsteeldetailing.com/UserFiles/files/15264370042.pdfIn PDF document text
    • https://zerling.eu/nico/images/files/1161423052.pdfIn PDF document text
    • http://phubozena.pl/userfiles/file/fibipajetogofida.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/34481546010.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-17/20210917015338279318.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/dd3c141e24e6645b36c91fe0b39a10ab/90596384778.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161301a998d152---18401474773.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138fb803b6bb---5609985674.pdfIn PDF document text
    • https://cometsecurity.in/admin/userfiles/file/78731492324.pdfIn PDF document text
    • http://lamgi.pl/ckfinder/userfiles/files/60567747617.pdfIn PDF document text
    • http://www.lentilles-progressives.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613b5830ec66e---rurijevoko.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/91464725734.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+get+trademark+symbol+on+androidPDF 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_off0000d238.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD238 19324 bytes
SHA-256: 6039132ca27777c0a5f02d2842b02c79006c11ab99ce175a5059838d311b6fe1
font_01_sfnt_off0001044f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1044F 11012 bytes
SHA-256: 7ad9a0a633f4f35537ef886e6712693e7c6ab8e440e53ead81fdabc77c8646fd
font_02_sfnt_off00011dbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DBE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1