Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac857cedefd42d68…

MALICIOUS

PDF

75.2 KB Created: 2021-09-29 10:55:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 01f86c5339b2466f47a64712b7462bf4 SHA-1: fb25bc9f01890346350ad0ef0ae6c346c691a74e SHA-256: ac857cedefd42d68455f9d1ab1184fbcc6e772351ea0553b7a4fad97bb1611c5
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to various websites, including those hosted on compromised WordPress installations. The presence of 'utm_term' parameters suggests an attempt to track user interactions, common in phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://drafthe.ru/uplcv?utm_term=007+ringtone+for+android PDF link annotation
    • http://sushi-belovo.ru/files/rakugijade.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109082158562988.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/16133eb9657a90---7631346499.pdfIn PDF document text
    • https://gazeta-msp.pl/user_files/File/89229502065.pdfIn PDF document text
    • https://www.democratum.com/wp-content/plugins/super-forms/uploads/php/files/28c9b9b810559db0e8c3c28a04f5a769/tesiliriribolatuxibe.pdfIn PDF document text
    • http://pusancard.com/userData/board/file/9038509479.pdfIn PDF document text
    • http://lachambredechos.com/userfiles/file/7481455256.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1614154d9425c1---98847548665.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/zixupafimonolurabusupema.pdfIn PDF document text
    • http://ineke-ott.nl/keramiek-beelden-imagesfile/13008412817.pdfIn PDF document text
    • https://wyslijpaczki.pl/app/webroot/files/userfiles/file/xubomokoje.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/25339449452.pdfIn PDF document text
    • http://sanfrancescovet.com/userfiles/files/zelakolofinafove.pdfIn PDF document text
    • http://ipublicity.cz/data/file/38285982687.pdfIn PDF document text
    • http://studiozoppini.com/userfiles/files/pixadukoxiduratogixepuzin.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/damitanovenu.pdfIn PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/65102233878.pdfIn PDF document text
    • http://recrute.fr/files/files/42845000510.pdfIn PDF document text
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/tomupapusimesuv.pdfIn PDF document text
    • http://gianniarnaudo.com/userfiles/files/7438855777.pdfIn PDF document text
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/54653610298.pdfIn PDF document text
    • https://bio-obst-und-gemuese.de/userfiles/file/vefesijotiruloladobabera.pdfIn PDF document text
    • https://satesayap.com/contents/files/9180996616.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_off0000bce5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCE5 19288 bytes
SHA-256: 64c7a5607ac657e6bb89e2d568ade9a91ef99e25dabad0eea56f3abb3b29a9d4
font_01_sfnt_off0000efbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBD 10392 bytes
SHA-256: a30e3adacb9bac93903a616d02ae1e96b5cfae159da71dc31a30955c470257d5
font_02_sfnt_off0001072d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1072D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1