Malicious PDF — malware analysis report

Static analysis result for SHA-256 e925170b08ca1316…

MALICIOUS

PDF

73.5 KB Created: 2021-09-24 22:01:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: bf067994c404fae12c2af4ee079777d6 SHA-1: ee4660edd302c8fcb8aa420a56ed335099156b30 SHA-256: e925170b08ca1316cc382fe2b681d2d98ec8c37e046a7e41d907978b3f98c5dc
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of external URI heuristics and link farm indicators strongly supports a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/161444b4bb369b---37663631987.pdf In PDF document text
    • http://wronba.com/uploads/wysiwyg/file/fosupezaxenoxuwevi.pdfIn PDF document text
    • https://hostsolutions.ro/app/webroot/files/userfiles/files/84245341170.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/7q9odiru0ulll3ig1cpvo0okp3/23804523332.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614ad8fe98a03---75862887781.pdfIn PDF document text
    • https://www.sexualaufklaerung-schule.ch/ck/ckfinder/userfiles/files/fibolexarinedarodik.pdfIn PDF document text
    • https://biblioteka-koneck.pl/ckfinder/userfiles/files/44109081144.pdfIn PDF document text
    • http://bebaldebaran.eu/userfiles/files/85186111012.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/030559287965.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/8b6ddb3e9bcbbca167af0a5bd39a1eef/mikor.pdfIn PDF document text
    • http://aias.pnu.ac.th/ckfinder/userfiles/files/4401674189.pdfIn PDF document text
    • http://confidenzacsapagy.hu/upload/sabopirade.pdfIn PDF document text
    • https://liepasmuiza.lv/userfiles/library/58579900493.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143e7c2cf7d0---11302769338.pdfIn PDF document text
    • http://heathrowairporttaxi.website/userfiles/file/41765946282.pdfIn PDF document text
    • https://pachetedeturism.ro/images/files/29519561335.pdfIn PDF document text
    • http://3wsystems.com/shipinc/userfiles/files/dodujapa.pdfIn PDF document text
    • http://plenerowe.kbo.pl/ckfinder/userfiles/files/29048601477.pdfIn PDF document text
    • http://haokunchem.cn/upload/files/50473726077.pdfIn PDF document text
    • http://parateam.cz/file/26535888992.pdfIn PDF document text
    • http://disonde.com/filespath/files/20210917132317.pdfIn PDF document text
    • http://marktoby.com/akram/know_news/admin/userfiles/file/78298322839.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/kexekoveni.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+save+pictures+on+memory+cardPDF 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_off0000b79d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB79D 18176 bytes
SHA-256: 690af44c0da3e1dd723271fc45def8c28f7eb370fba7f1f03232065d7dac4d7c
font_01_sfnt_off0000e67f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE67F 10984 bytes
SHA-256: 8ba201eab640489c42126eee7cede2d6e6431edf749b89c232f6967e3dfe3b0d
font_02_sfnt_off0001000e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1000E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1