Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf18746664477e80…

MALICIOUS

PDF

80.2 KB Created: 2021-09-21 08:13:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 4e8e1adb84ac5dd574b3639ddf4acbe5 SHA-1: 7d1c874013398c4944d1e69dbf0628981f71ac90 SHA-256: cf18746664477e8006c5b9d22bf0a3b0db870159ea032377f42d191855e109a8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the PDF structure itself is used to host and distribute these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://nomylo.ru/uplcv?utm_term=moto+g+5g+plus+software+update PDF link annotation
    • http://ctnphrae.com/ckfinder/userfiles/files/49490623605.pdfIn PDF document text
    • https://ww150006.linebot.net/upfile/files/20210908140313.pdfIn PDF document text
    • http://chochosanencino.com/uploads/files/raxexowafiv.pdfIn PDF document text
    • http://rvhifi.cz/files/file/28931452789.pdfIn PDF document text
    • http://3q1p.com/upload/file/210909171357408896spilmp13whvl.pdfIn PDF document text
    • https://combrooncom.com/contents/files/32681861854.pdfIn PDF document text
    • http://gmtshipping.com/attachment/file/78150483773.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1614458dd620c3---94244391962.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/77861905429.pdfIn PDF document text
    • https://pleasanton.com/wysiwygfiles/file/80806612594.pdfIn PDF document text
    • http://wellfoto.cz/pictures/files/pidovaxipedufadukori.pdfIn PDF document text
    • http://powercleanperu.com/cms_powerclean_2015/sgi_userfiles/userfiles/files/31000691823.pdfIn PDF document text
    • https://netcsemege.hu/ckfinder/userfiles/files/gusukewikuvupajawo.pdfIn PDF document text
    • http://packturf.fr/files/92783285803.pdfIn PDF document text
    • http://khmim.com/ckfinder/userfiles/files/41128709671.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/66698a457f01b4f8516a74e000f2d872/gididise.pdfIn PDF document text
    • https://businesslife.com/content/file/87646865185.pdfIn PDF document text
    • https://schmitz.cz/res/file/gizupunukagowizukel.pdfIn PDF document text
    • https://censcakmu.org/board/file/files/nufaxepatofaleriwufixem.pdfIn PDF document text
    • http://graphicyazd.com/ckfinder/userfiles/files/86967657463.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e32a317642---kaxivutimubikeb.pdfIn PDF document text
    • https://sentinels.ro/userfiles/file/tudekoludenamajubederegit.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_off0000d2a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2A7 17508 bytes
SHA-256: 79f5403794f06aa4c69aaf471e4dcbddccf71edbe6d075d1f1e22eb26df46cd9
font_01_sfnt_off00010098.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10098 10788 bytes
SHA-256: a1ce6107c4cf85f684f1f2e54be565ee5a7f297d3f486d8a19cb4a2e25a34bcf
font_02_sfnt_off00011996.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11996 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1