Malicious PDF — malware analysis report

Static analysis result for SHA-256 51e1cfd79abaae13…

MALICIOUS

PDF

75.9 KB Created: 2021-09-20 00:21:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 0fd3e98a985a85fd2cf1592264ef3f5e SHA-1: 9b7e6ceb3b240ba65b40760fcc102cef51ffc150 SHA-256: 51e1cfd79abaae130a0e0ab95d84cf9fa334311a29b0bd3aac093d30e6eee751
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of a link farm pointing to disposable hosting or compromised CMS uploads, indicating a phishing or scam attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://infrive.ru/uplcv?utm_term=jab+harry+met+sejal+full+movie PDF link annotation
    • http://eskuvoiiranytu.hu/blog/file/91229637554.pdfIn PDF document text
    • https://currenwatch.myhost360.cn/file/upload/files/09-01-07-57-53-20.pdfIn PDF document text
    • http://www.heksan.com.pl/file/39516245731.pdfIn PDF document text
    • https://venusnvs.com/userfiles/file/7647706587.pdfIn PDF document text
    • http://mawratanews.com/armedia/uploads/files/90213539996.pdfIn PDF document text
    • http://toyotacri.com/userfiles/files/pafuzokavitajinonefikopek.pdfIn PDF document text
    • https://darkoyunpin.com/calisma2/files/uploads/manogifufanuboladotawal.pdfIn PDF document text
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/60135554873.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/cf5e43a588ce03b415e5b856065e1ae2/1974615511.pdfIn PDF document text
    • https://247christianity.org/fckeditor/userfiles/file/zawopubowotumixu1631037791.pdfIn PDF document text
    • http://ahppesticide.com/userfiles/file/gifotibebige.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/6a0aa0829e3219942a6d4a01c278ce26/81411170111.pdfIn PDF document text
    • https://alsultantrading.ae/userfiles/files/lokuzilaronodujebed.pdfIn PDF document text
    • http://mobilesamara.com/img/files/file/14591103503.pdfIn PDF document text
    • https://totspotdaynursery.co.uk/ckfinder/userfiles/files/37487902542.pdfIn PDF document text
    • http://yejiya.com/userfiles/file/rifuvitowusuvowalositeg.pdfIn PDF document text
    • http://rustproofingottawa.com/userfiles/file/8154115281.pdfIn PDF document text
    • http://worldnaturalfood.com/image/upload/File/98822466811.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161326816aa9cd---3682971510.pdfIn PDF document text
    • http://ancient-theater.gr/media/file/fumiwarupetinuvemisusowa.pdfIn PDF document text
    • https://huaku3c.tw/uploads/files/202109101923083826.pdfIn PDF document text
    • https://ystechpro.com/nbloom/fckuploads/file/59428847031.pdfIn PDF document text
    • http://edisonprivateschoolbeta.com/cote_dor_import/admin/ckfinder/userfiles/files/wafobujarutu.pdfIn PDF document text
    • https://mgrenginiai.lt/ckfinder/userfiles/files/lufinawiwowofetimuv.pdfIn PDF document text
    • http://pomelieagency.com/userfiles/files/36500029430.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_off0000c27b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC27B 10916 bytes
SHA-256: a4e7527c8437aa3bcf1b105fbadd6d7f026c221763af2d8ca1a2b3e6cf24aef2
font_01_sfnt_off0000dbc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBC9 17712 bytes
SHA-256: 5fcfa3eac780c3f0f240ffcb624483ce5e97c3c39bdfdb304b683295f195b03b
font_02_sfnt_off00010a48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A48 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1