Malicious PDF — malware analysis report

Static analysis result for SHA-256 e98554fce7106d31…

MALICIOUS

PDF

80.6 KB Created: 2021-09-17 13:46:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: d71e9beb95aa9b52df0d204aef253729 SHA-1: 85b9aec0470359832e8d64591e52c4c28633cc2c SHA-256: e98554fce7106d31b66ead0e9fba3c91df180e090e6ae966c06f769f49d1c85c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics indicates a pattern of using PDFs to host a large number of links, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://inwebjor.ru/uplcv?utm_term=galaxy+skin+new PDF link annotation
    • http://paraleumarian.ro/app/webroot/files/userfiles/files/82720984387.pdfIn PDF document text
    • http://sashtraayurveda.com/ckfinder/userfiles/files/53069078226.pdfIn PDF document text
    • http://qdxqw.com/uploadfile/file/12484791252.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/85739426986.pdfIn PDF document text
    • https://lostsoulsmemorialnj.org/wp-content/plugins/super-forms/uploads/php/files/2b67460a6c3cf804d6e7b168a2a07b86/tijutipotero.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/8e1290803ea11a144ac19eac71f62f74/rumufipe.pdfIn PDF document text
    • http://netart.hu/userfiles/file/sijafekapinidatebofu.pdfIn PDF document text
    • http://shop-cartuning.pl/userfiles/file/faxes.pdfIn PDF document text
    • http://birdwatching.sk/media/file/xukaz.pdfIn PDF document text
    • http://xn--80aafbjcazdrhzgiddbbcsg4l.xn--p1ai/pict/file/8118794231.pdfIn PDF document text
    • http://vip-cond.ru/userfiles/file/83210641049.pdfIn PDF document text
    • https://creativitagh.com/pevron/www/img/file/buteboned.pdfIn PDF document text
    • https://thefertilizergranulator.com/d/files/40682576465.pdfIn PDF document text
    • https://pro-biomed.com/admin/userfiles/file/22829292069.pdfIn PDF document text
    • http://kamkmori.cz/ckfinder/userfiles/files/1670992009.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d511aa24b8---gopokesepamel.pdfIn PDF document text
    • http://makassitools.com/userfiles/file///pilewudaxogabe.pdfIn PDF document text
    • http://lamorenj.com/userfiles/files/37120357071.pdfIn PDF document text
    • http://2017.letnifestiwal.pl/ckfinder/userfiles/files/60379986231.pdfIn PDF document text
    • https://reparationmobile.net/userfiles/file/dogavexusirigufem.pdfIn PDF document text
    • https://ikorti-iao.com/userfiles/files/77665391407.pdfIn PDF document text
    • http://teakdeck.pl/files/file/zesetivaduwef.pdfIn PDF document text
    • https://tsolisp.com/files/file/83045412161.pdfIn PDF document text
    • http://fitviewer.com/files/file/5245759670.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/161332afe36d10---dupuwinifeluzuledagu.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_off0000d963.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD963 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF175 17396 bytes
SHA-256: c5ce33a2a32fab97e405c1a5938e2652d6f838e1e6472df98063e34a4f8751db
font_02_sfnt_off00011e07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E07 10216 bytes
SHA-256: ac2d54b637dcc00f91341b26259b2f7daa763d1fe3bc8555417fe4a1a1257df6