Malicious PDF — malware analysis report

Static analysis result for SHA-256 d51ebe2434ae3a20…

MALICIOUS

PDF

71.4 KB Created: 2021-09-19 02:57:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 736d362201dbf766411fe0f6a6032fb0 SHA-1: f81ea8be920d2007309f3f1ab3e7ce367e313e6c SHA-256: d51ebe2434ae3a20856de4eb6b99330514efc0cc6adabd051b29ceea9c5e87b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised or disposable domains, suggesting a phishing or malware distribution scheme. The ClamAV detection and ML classifier strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of malicious activity, likely aiming to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://nomylo.ru/uplcv?utm_term=best+video+editing+app+for+android+download PDF link annotation
    • http://ud2-140.com/files/gasofokor.pdfIn PDF document text
    • https://yodobashi-church.com/romiturofolagogurivudi.pdfIn PDF document text
    • https://mmgrowersg.com/ckfinder/userfiles/files/lubewufibikukizigi.pdfIn PDF document text
    • https://ehlibeytalimleri.com/resimler/files/gezigij.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bfd5d3c40e---60594202197.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/3c766835f6e5a347be9e2c84de1d8543/46521652659.pdfIn PDF document text
    • https://pilot-nav.socksnbows.com/ckfinder/userfiles/files/55334280982.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/772cb9d9347a5167819848670ce67ff7/18830260110.pdfIn PDF document text
    • https://niboparis.com/upload/fckeditor/file/1631805944_1.pdfIn PDF document text
    • http://tsrmvolontari.it/userfiles/files/mugizawupuzafavo.pdfIn PDF document text
    • https://dijitalsanat.link/upload/files/paradesejil.pdfIn PDF document text
    • http://engcaphone.com/_UploadFile/Images/file/94236679943.pdfIn PDF document text
    • https://dalba.net/other_files/File/wotexufekewaxobe.pdfIn PDF document text
    • https://autoprofi.ua/userfiles/file/kagelezokazimute.pdfIn PDF document text
    • https://maintogelonline2.org/contents/files/5512476203.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/rtgh5jd4rocrig6c02k9di6le3/59334209959.pdfIn PDF document text
    • http://tercovci.cz/files/file/52939156622.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/mutagejajerexorobuw.pdfIn PDF document text
    • http://ge-mak.com/files/kiwawibejetaturotoxarige.pdfIn PDF document text
    • https://drlanda.hu/user/file/85013255466.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133dbdeb44a3---38781632556.pdfIn PDF document text
    • http://ingegnasrl.com/userfiles/files/33299997007.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_off0000b4e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4E7 16472 bytes
SHA-256: d0a405885dcf087400e070861198177871427ed1c4a5356f43ca035c4b5b0217
font_01_sfnt_off0000ded6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDED6 10880 bytes
SHA-256: 8e9380dc826973b94e17a953ceb37295f293749e6fc41c8330708918a34818b6
font_02_sfnt_off0000f803.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF803 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1