Malicious PDF — malware analysis report

Static analysis result for SHA-256 d6fd5e55769b6d8e…

MALICIOUS

PDF

86.4 KB Created: 2021-09-19 06:49:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: a9c71c9dd7346f6cbb6cdb1cfca79958 SHA-1: 9b33052d067062a1bd9bb7004c19b50269c856a7 SHA-256: d6fd5e55769b6d8e727b11212aa470b817272e36191d90b803abef5971badc5b
126 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm on disposable hosting, with numerous external URIs pointing to potentially malicious content. The presence of embedded URLs suggests an attempt to redirect the user to external sites, likely for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://coretry.ru/uplcv?utm_term=3d+gallery+app+download PDF link annotation
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613e7ee143d4b---mosalogazuvoki.pdfIn PDF document text
    • http://alessandrobelleseveterinario.eu/userfiles/files/77482394133.pdfIn PDF document text
    • http://3bbb.fr/ckeditor/upload/files/dusejopuzarulamuludub.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/kifizokezenibolib.pdfIn PDF document text
    • http://kolesnikov.pro/ckfinder/userfiles/files/23131709378.pdfIn PDF document text
    • http://zhengfutz.com/v15/Upload/file/202197109343224.pdfIn PDF document text
    • https://osakadentalcare.com/contents/files/sabuvetarapidomido.pdfIn PDF document text
    • http://lynxitservices.com/ckfinder/userfiles/files/fososuxutikaz.pdfIn PDF document text
    • http://stattus.com/assets/file/50422588855.pdfIn PDF document text
    • http://desiaussies.com/ckeditor/uploads/files/37751296220.pdfIn PDF document text
    • http://biolabsrl.org/userfiles/files/nufufodizumaremasexebota.pdfIn PDF document text
    • http://csc0512.com/userfiles/file/20210903223027_v4nbut.pdfIn PDF document text
    • https://yk-tech.com.tw/ckfinder/uploads/ckfiles/files/puwatusepulajovalixu.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/65625700059.pdfIn PDF document text
    • http://topmebli.com/content/xuploadimages/file/36745479659.pdfIn PDF document text
    • https://arte-salon.ru/upload_picture/kofudunu.pdfIn PDF document text
    • http://kukubara.com/zdjecia/file/tekiz.pdfIn PDF document text
    • http://reelproductionshd.com/userfiles/file/40779303095.pdfIn PDF document text
    • https://majubesar.com/contents/files/satubugevujunogofumar.pdfIn PDF document text
    • http://dejede.com/userfiles/file/52639672115.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/161434cf6948fe---mojes.pdfIn PDF document text
    • http://gardena.crazyrockinsushi.com/uploads/files/nuget.pdfIn PDF document text
    • http://arkystudio.eu/userfiles/files/76452015835.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///bibarewisebobepo.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_off0000ebc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000103dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103DC 10484 bytes
SHA-256: 83abe8684da2d19da8ce58f54dcb629d1951cab5813d2490a0a182a43cfdf35c
font_02_sfnt_off00011b97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B97 18464 bytes
SHA-256: ad266fa0d87793ae5c0ef3f9290d373bf8e2720a2d2d14d3c4c480b0c9bc7f4f