Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b1397e47b15d4bc…

MALICIOUS

PDF

142.2 KB Created: 2021-09-01 12:33:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 507488bb4d6a0b356813f58f96ec88e0 SHA-1: fa888a284bfcf7de5ac83efaab410a5b8aac19fc SHA-256: 8b1397e47b15d4bc2bc2ba45a7188e23d2f1e0aa0821bcd1ca0bfa542bdd8a5e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9736

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://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bba04676cb4---90300472167.pdf In PDF document text
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/a73b50641d8171d32361fcfeb1b04201/visinojanelanovije.pdfIn PDF document text
    • http://vitalbafitnessclub.eu/userfiles/files/43481320068.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/jbf1q5t661hko2hfnv233sihmp/tuxax.pdfIn PDF document text
    • http://www.lauricedale.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160bbf36f987e4---tavufiwuxomomule.pdfIn PDF document text
    • http://nikacarpet.com/My_Project/Hamishe_bahar/ahar_img/files/88076489601.pdfIn PDF document text
    • http://alphasigmaoverseas.com/userfiles/file/4624385569.pdfIn PDF document text
    • http://basumati.com/app/webroot/ckfinder/userfiles/files/bezevolipazonekopi.pdfIn PDF document text
    • http://abwcoliseum.com/uploads/files/govutedeb.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d90441b2ef---77092292673.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be8f9cc956d---20326238048.pdfIn PDF document text
    • https://hospvetcentral.pt/site/upload/file/25439786913.pdfIn PDF document text
    • https://svingenieria.cl/userfiles/file/parawuvo.pdfIn PDF document text
    • http://ags-sib.ru/ckfinder/userfiles/files/87840145632.pdfIn PDF document text
    • http://dongshengcable.com/images/upload/File/pizubofejom.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/xupanijabupoladol.pdfIn PDF document text
    • https://saftanton.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b3c8ebd09---80273137189.pdfIn PDF document text
    • https://hainutedecopii.eu/ckfinder/userfiles/files/50984157871.pdfIn PDF document text
    • https://stillwaiting.org/userfiles/file/jesomejenoboruj.pdfIn PDF document text
    • http://archinfo.ru/uploads/file/xitalitefuvivijeru.pdfIn PDF document text
    • http://anandtouristcorporation.com/uploads/dojupifofazenuvopajobo.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/todegisilorewuwobo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=science+puzzlers+twisters+%26+teasers+answer+keyPDF 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_off0001c63b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C63B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001de4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1DE4D 19852 bytes
SHA-256: ed0c02590fe1e2cd21ca375937c3ae1ca6eaa1326225a3f81e0960de140613bf
font_02_sfnt_off00021215.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21215 10404 bytes
SHA-256: a6f88a6ed2fff933bf50ddc07b7ccb74969d637bcd7c451f5806aef15612b6a1