Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c7f8c1e36ebc29a…

MALICIOUS

PDF

73.6 KB Created: 2021-09-28 14:49:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 3ea6fa777e181f191744193207164ac8 SHA-1: ca4f4459c58a3dc13ec28c775cf95dba4a158651 SHA-256: 8c7f8c1e36ebc29a34fff827e38bab91418a1467d9a97413159d0d3b931c1712
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and links to compromised CMS uploads, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of multiple distinct hosts and UTM parameters in URLs points towards a coordinated effort to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

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://philabc.ru/uplcv?utm_term=prince2+project+management+methodology+pdf PDF link annotation
    • http://zoltysnieg.pl/pliki_wyswig/files/gunamurarajekovu.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/68813292471.pdfIn PDF document text
    • http://www.phuongdonggolf.vn/app/webroot/uploads/files/xukalazug.pdfIn PDF document text
    • http://mobil-tech.com/files/79415138251.pdfIn PDF document text
    • https://riolospettacoli.it/filesUploads/file/69916886427.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614eb4035bd99---vaxebadonavadep.pdfIn PDF document text
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/zolubisigubuwezibumewive.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/duzarinifoporebaledefewe.pdfIn PDF document text
    • https://nezamirekhaseafoods.com/userfiles/file/38924479950.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/kofcck7gnqfo9g6rkub7vcd1t0/54300705279.pdfIn PDF document text
    • http://beming.com/ressource/site-image/files/22955094202.pdfIn PDF document text
    • http://www.psoevalledeabdalajis.es/ckfinder/userfiles/files/81736904753.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613062d31f6f8---30888388277.pdfIn PDF document text
    • http://anipetkingdom.com/webroot/img/files/vewobetenopevegivut.pdfIn PDF document text
    • http://capital96.com/userfiles/file/tedilifijijijataj.pdfIn PDF document text
    • http://concilianavarra.com/userfiles/files/jovaradedi.pdfIn PDF document text
    • http://pc580.cn/upload_fck/file/2021-9-21/20210921013428337919.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/5a0h5j3hb4puosil1rkgl1a5e1/vevojunifo.pdfIn PDF document text
    • http://hongphuc.vn/userfiles/file/24515873389.pdfIn PDF document text
    • https://wct.goldcrownresort.com/magazine_files/files/81865730238.pdfIn PDF document text
    • http://decaiyun.com/upload/file/210912052909708846p35wgjdufm27.pdfIn PDF document text
    • https://kebecelectrique.com/upload/editor/file/69196424236.pdfIn PDF document text
    • http://markasib.ru/ckfinder/userfiles/files/galabixibavonemefu.pdfIn PDF document text
    • http://bandenplaats.nl/cmsimages/file/xeranuzaw.pdfIn PDF document text
    • http://dinskayarealty.ru/media/file/56357012078.pdfIn PDF document text
    • http://residencelesaline.it/userfiles/files/tijolonagamo.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_off0000b7f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB7F9 11264 bytes
SHA-256: 9350eefd444db797a336826619c7eabf2483d8225bb9bded1e948baf83063fa4
font_01_sfnt_off0000d204.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD204 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ea16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA16 18144 bytes
SHA-256: d3460c6b4eba7f335c29498f3610c7c8ea39aa7d100272afac7dc24e6f0a95b5