Malicious PDF — malware analysis report

Static analysis result for SHA-256 88adcce6af5e67fe…

MALICIOUS

PDF

83.7 KB Created: 2021-09-10 21:22:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c46075f03a47d2a0f532a7dd7f158b49 SHA-1: 46bcc1ed1c0fedf2d2c25d8958d838d52de0b582 SHA-256: 88adcce6af5e67fe17472e67d4c584d7c4b98a17cfcc7e928ecc4e0c10f1a8fb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF functions as a link farm, directing users to various external websites, some of which are hosted on compromised or disposable domains. The embedded URLs suggest an attempt to distribute phishing content or further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://coumert.com/images/file/febofuwixafekuxi.pdf In PDF document text
    • http://ieeepes-thailand.org/app/webroot/files/files/petewi.pdfIn PDF document text
    • http://sanmorales.es/userfiles/files/49101904373.pdfIn PDF document text
    • https://wasael.com/userfiles/file/poradavogiv.pdfIn PDF document text
    • http://budka39.ru/files/67355176160.pdfIn PDF document text
    • http://jtravel.clickis.kr/FileData/ckfinder/files/20210905_C3E90F4F93EFF600.pdfIn PDF document text
    • https://il-gusto.com/images/file/20446881216.pdfIn PDF document text
    • https://petrovsky14.ru/docs/files/6672527768.pdfIn PDF document text
    • https://kingyao.com/uploadfiles/files/20210906_134433_4897.pdfIn PDF document text
    • https://bitree.com/ckfinder/userfiles/files/fawamulo.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/161383ffa8cb58---24117489746.pdfIn PDF document text
    • https://muzpony.de/obrazki/file/85563212261.pdfIn PDF document text
    • http://www.dilipprabhavalkar.com/images/file/towetowanemisurexetikixa.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/jowegaxe.pdfIn PDF document text
    • http://abnig.friendship-match.com/upload/files/topigenafakekorofumivinuz.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/42827618340.pdfIn PDF document text
    • http://anpharma.net/upload/files/76804307507.pdfIn PDF document text
    • https://dadesigning.com/daduserfiles/files/gopujerizet.pdfIn PDF document text
    • http://hoya-system.com/uploads/files/202109050523197728.pdfIn PDF document text
    • http://www.rafaellucenaehijos.com/ckfinder/userfiles/files/bagetexuvoxidunotexobidet.pdfIn PDF document text
    • https://ta-taiwan.com/app/webroot/userfiles/files/bezuwaju.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16137641cda2fe---31241159379.pdfIn PDF document text
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138555b231bd---61887118925.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/1oif4l6agsucovcts33ovuigt5/xukugejix.pdfIn PDF document text
    • http://www.klimavill.com/data/editorfile/zukafabed.pdfIn PDF document text
    • http://think6.net/ckfinder/userfiles/files/20210910191832.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=indian+rail+apps+for+androidPDF 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_off0000e429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE429 17732 bytes
SHA-256: b2d3750e07d05057d4d40d43eb517fe6dbdc5db042abf27c1e63a3093399e9fb
font_01_sfnt_off00011206.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11206 10212 bytes
SHA-256: b91f19bc6ce88396ddd2596f3d40b70552a99c4e61f1d3f13387598a4e93bba6
font_02_sfnt_off000128ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128ED 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1