Malicious PDF — malware analysis report

Static analysis result for SHA-256 39da0c2d36549b81…

MALICIOUS

PDF

83.6 KB Created: 2021-09-09 16:32:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f0c25578b412ba92b0b765843850a155 SHA-1: 77f56b450c959d66445e288a479edb7e492e3622 SHA-256: 39da0c2d36549b81312bfbe49b823445a4486eff0478726f65d3079df107a719
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS platforms. The presence of numerous URLs, many pointing to PDF files, suggests an attempt to distribute malicious content or phish for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://wastran.ru/uplcv?utm_term=what+is+flipfont PDF link annotation
    • http://nirmalapublicschoolerumely.com/userfiles/file/23182917193.pdfIn PDF document text
    • http://hamzalegalservices.com/userfiles/file/sonimozilanoxuze.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/41029277563.pdfIn PDF document text
    • https://tnmkor.com/FileData/ckfinder/files/20210909_3A87B36ACC6A7162.pdfIn PDF document text
    • http://hobbes-group.com/upload/files/55246233185.pdfIn PDF document text
    • http://movietek.vn/hinh-anh/files/19135624230.pdfIn PDF document text
    • https://gilbertems.com/videos/file/2187308498.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/tagokexutujize.pdfIn PDF document text
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613755d013b0a---pirini.pdfIn PDF document text
    • http://movitecnic.com/ressource/site-image/files/gezugelodafafiseno.pdfIn PDF document text
    • https://kapokcmassage.com/uploads/files/202109041029438467.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613820994bc92---komix.pdfIn PDF document text
    • https://saatyapi.com/upload/ckfinder/files/83422758385.pdfIn PDF document text
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16132fc4b98153---pijaketukomilofifikozaz.pdfIn PDF document text
    • http://debschoen.com/userfiles/file/37278380845.pdfIn PDF document text
    • http://leeharringtonhomes.com/userfiles/file/dutamivovifuka.pdfIn PDF document text
    • https://thinkglobalcompliance.com/ckfinder/userfiles/files/boxegofura.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/65914771135.pdfIn PDF document text
    • http://keyflounge.nl/userfiles/file/zeledetewudesanizarupe.pdfIn PDF document text
    • https://0900107678.com/upload/file/napibaf.pdfIn PDF document text
    • http://insureavisitor.com/userfiles/file/kivanezakepifezet.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/10994998787.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/tezotek.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_off0000e202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE202 10216 bytes
SHA-256: 1892833d461c1ded4a6deda6f9baf6838fd386dabe8f1747dc03ebc395704afa
font_01_sfnt_off0000f8db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8DB 18412 bytes
SHA-256: 996204cbc0a0a16b7138ef51215f8cad1de2e45adfc51ca856f4ec5ee3e104c6
font_02_sfnt_off00012939.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12939 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1