Malicious PDF — malware analysis report

Static analysis result for SHA-256 043622aa69034d67…

MALICIOUS

PDF

81.7 KB Created: 2021-09-14 18:04:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e111111cd3c412a66fd7e0d95dd9ef6c SHA-1: ccc49ca0bc527cecdffeebf94323b37346089382 SHA-256: 043622aa69034d67b88ee91ff487f873b4adabc7bbc460abebb128c04ea35e05
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 or are part of link farms on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of external URI heuristics and the compromised CMS upload link firing support this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://philabc.ru/uplcv?utm_term=download+phoenix+apk PDF link annotation
    • http://client.diffuse.info/files/fakubiwoxivojibuw.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161401a986c92e---24173270295.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/bawazaxosaraxotomomuje.pdfIn PDF document text
    • https://gmnavarra.es/ckeditor/files/8440030048.pdfIn PDF document text
    • http://zoncmswebsitebeheer.nl/files/editor/file/xevisamemexabo.pdfIn PDF document text
    • http://kkagro.com/media/images/upload/file/pimupijogupewesezasitini.pdfIn PDF document text
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/zusiliribat.pdfIn PDF document text
    • http://gzhangqin.com/uploadfile/files/9243346722.pdfIn PDF document text
    • http://lagrupacio.cat/file/nilipinujod.pdfIn PDF document text
    • http://a-pluset.com/userfiles/puteruzo.pdfIn PDF document text
    • http://sdv.sk/userfiles/articles/file/2401001840.pdfIn PDF document text
    • http://yeosingol.com/FileData/ckfinder/files/20210912_45947B8698AEF4B4.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bab170adbc---29584408373.pdfIn PDF document text
    • http://mamolenasnc.it/userfiles/files/padimowodifovesetakax.pdfIn PDF document text
    • https://goldengatetaichiqigong.com/userfiles/file/refan.pdfIn PDF document text
    • http://kvrhousing.com/uploads/33825615082.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0335b8f09---270927689.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/55656399065.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/450qedq5i4sug772d2m1sps5i2/soranikofesozunigixizu.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/bovulaxali.pdfIn PDF document text
    • http://rheinmotel.com/userfiles/file/4538045498.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/bopivuwediwewes.pdfIn PDF document text
    • http://f-okinawa.com/img/tmp/file/42240608239.pdfIn PDF document text
    • http://jandebruijn.com/uploadimages/files/tamurosobesut.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_off0000d8f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8F5 18828 bytes
SHA-256: a5a3dac3679007bfcdad54c0ad2a02c74791e200cfa1993bbd8891d8e0f25742
font_01_sfnt_off00010a55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A55 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001226c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1226C 10404 bytes
SHA-256: 9322a08f2abd5ff91fdc7c882ac0cfc4efe924c74ca750bfd8efef79b33eaf06