Malicious PDF — malware analysis report

Static analysis result for SHA-256 31709e7807217951…

MALICIOUS

PDF

80.9 KB Created: 2021-10-04 21:15:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 66050df5f2789b785194483e4258a38d SHA-1: 89214fca36289c8fd3f07c223e54bf1128831f57 SHA-256: 31709e7807217951987b82ff94988efb2bbc5486b8185185cdd7505eb768f806
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicative of a link farm used for phishing or malware distribution. The presence of embedded JavaScript further suggests malicious intent, likely to facilitate the redirection or execution of a payload. ClamAV detection and ML classification strongly support the malicious verdict.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://garglob.ru/uplcv?utm_term=shock+and+dic PDF link annotation
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109280212517468.pdfIn PDF document text
    • http://skalamatbaa.com/userfiles/file/68316494143.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/21887770922.pdfIn PDF document text
    • http://www.gamylai.vn/uploads/files/9696732345.pdfIn PDF document text
    • https://jahanchart.ir/data/files/file/bowobufexij.pdfIn PDF document text
    • http://zvezda-rostov.ru/ckfinder/userfiles/files/83453754514.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/50162686694.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613430b619f59---bejofijanajitufukafigofuv.pdfIn PDF document text
    • http://giteduguedesboires.com/userfiles/file/60322212937.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/64738029050.pdfIn PDF document text
    • https://treasurehunterdetectors.solar-ovens.net/ckfinder/userfiles/files/1749670493.pdfIn PDF document text
    • http://puebloexec.com/userfiles/file/jixadolisadorexo.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16141142ac4bc9---27741887971.pdfIn PDF document text
    • https://nationalshield-uae.com/userfiles/files/nelezekaxojat.pdfIn PDF document text
    • https://thucphamtruongxanh.com/Upload/files/diragu.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/161532ec741cde---vasiridi.pdfIn PDF document text
    • http://123flower.doweb.kr/upload/files/78687416488.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/161529fb3d9fb5---lofugelomepubemo.pdfIn PDF document text
    • http://www.stsmcc.org/www/js/ckfinder/userfiles/files/58448404774.pdfIn PDF document text
    • http://movitecnic.fr/ressource/site-image/files/1614980528.pdfIn PDF document text
    • http://www.ags-sib.ru/ckfinder/userfiles/files/4344768275.pdfIn PDF document text
    • http://maximaviajes.com/FCKfiles/file/91194686681.pdfIn PDF document text
    • http://xn----itbbfrdrdbd4bgy6gi.xn--p1ai/webroot/files/files/87854773687.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_off0000d52e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD52E 19284 bytes
SHA-256: 8b4804f49461253b67c44ee29dd11c0feec2e5c8245513b3c121faf5a1690c9b
font_01_sfnt_off000107e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107E8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FFF 10088 bytes
SHA-256: bd0426c2bee6568357a76b13abf469b1512dfde719fb85b2c6338254cfcbee57