Malicious PDF — malware analysis report

Static analysis result for SHA-256 31e24f06f984b3fd…

MALICIOUS

PDF

100.1 KB Created: 2021-06-27 05:25:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 6b066da526e82d757466930614a17dbb SHA-1: 78d2bac23dd5164a77022f34b0eb8e80e3b42435 SHA-256: 31e24f06f984b3fdda437767202ad43edd54c883b2879f4faa6d906b4587ba2a
156 Risk Score

Malware Insights

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

The PDF file contains numerous links, many of which point to compromised WordPress upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these external links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://paymentsbusiness.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160773ccf6fe32---1787728984.pdf In PDF document text
    • http://cukierniabrzezinski.pl/www/artizam/fck/file/95769524481.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c717fa40d48---32143781455.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cc9534bac2---32113797737.pdfIn PDF document text
    • http://seamcc.com/UserFiles/files/84134635210.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ed15feab1c---14028014064.pdfIn PDF document text
    • http://www.franklinwebdesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a778989f99a---rigovegi.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082805b99062---jarogerotubivov.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072a91c8c498---dafuwugokowix.pdfIn PDF document text
    • http://bangtaisay.com/uploads/userfiles/file/85011968113.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/dac187b731afb51fe1ef802acc4745f9/vudisovilinerigatamarinok.pdfIn PDF document text
    • http://tamker.hu/userfiles/file/xuzepaxoguzabi.pdfIn PDF document text
    • https://termoformat.md/img/files/wasifagibijolad.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b811e09bbcc---ketebajuvolif.pdfIn PDF document text
    • http://maility.pl_adresuserfiles/file/89893575443.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/cjopqfei21t2i4452rcn49r462/82276753435.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/83v4opgdjkmf2tdnvf1l2pr4pb/xuruzirofidezafidutanob.pdfIn PDF document text
    • http://tortsurprise.ru/upload/redactor/files/77744581913.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/6bde9792e418dac6b5a98e90ff731006/fitulesudajojovuwizadu.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/54589531878.pdfIn PDF document text
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/ab4c5036463a7aa2305d47aa2986bee6/poputuzugo.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077efe2a4a3b---vijibugefogabusa.pdfIn PDF document text
    • http://tillmanfamilyreunion.com/clients/b/b7/b7385abc5988d1ee605fea7695e3d00e/File/60750171724.pdfIn PDF document text
    • https://skinrepublic.vn/webroot/img/files/gopolutobaxaweful.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=impact+scholarship+for+black+studentsPDF 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_off000122f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122F5 17728 bytes
SHA-256: 66fd4bdd37bc6829e5c621429b182a0d6198e9257e1803b3de7dc6c565b1a40f
font_01_sfnt_off0001512e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1512E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016945.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16945 11168 bytes
SHA-256: 75ee3283d621fbaec298c1d4ce0a31cd1f6bcef9c5c1155fc6bfb4f2a1e5209f