Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a3b0d38df214888…

MALICIOUS

PDF

74.5 KB Created: 2021-09-08 17:16:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: dc85638c82e4d5c28c46c590cd5f4f76 SHA-1: 5d74b8368ade1969edd20b680e3f33ffc9acff08 SHA-256: 5a3b0d38df214888150c181cf5cb3ee6fe8e2c44fed9afddc223f92c03c79818
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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=excel+all+formula+list+with+examples+pdf PDF link annotation
    • http://chrisdepanneservices.fr/Sites/cds/files/dodudanurunojorapu.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/wisijatitaworobudosav.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/161329fdf6be65---gijedesuvosevo.pdfIn PDF document text
    • https://bselink.com/userfiles/file/95843898793.pdfIn PDF document text
    • http://www.jasfec.com/imgs/uploads/lidizubatojuputozodiguvi.pdfIn PDF document text
    • http://nacyc.jp/Upload/file/wudugamutuzutog.pdfIn PDF document text
    • https://ambalatender.com/upload/files/59618465877.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/4c045477592d4d2d8a9f428e97649592/52373072265.pdfIn PDF document text
    • http://mondoacquapiscine.com/userfiles/files/nujanejopogamaba.pdfIn PDF document text
    • http://wawabed.pl/uploads/userfiles/file/54374398354.pdfIn PDF document text
    • http://eros-arena.name/eros/userfiles/file/58307802516.pdfIn PDF document text
    • http://huspanda.com/data/ckfinder/files/26855199347.pdfIn PDF document text
    • http://mh-gartengestaltung.de/userfiles/file/ketemaripafesixodapev.pdfIn PDF document text
    • http://www.oneworldkarate.com/fckeditorimages/userfiles/file/favufisavazinitolitupava.pdfIn PDF document text
    • http://nhactheducthammy.com/upload/files/86780542375.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea67ea01a1---japitotojogu.pdfIn PDF document text
    • http://keacg.com/upload/files/58550661069.pdfIn PDF document text
    • https://njsolarpower.com/wp-content/plugins/super-forms/uploads/php/files/56b03ee27b5f4359d94895bb88cea274/75515103339.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/pesub.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613462cd7bac2---99350609045.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/basakizefemogez.pdfIn PDF document text
    • https://apsco.ly/userfiles/files/13945482769.pdfIn PDF document text
    • http://elektrostroy.kz/ckfinder/userfiles/files/16125898217.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_off0000c08e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC08E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d8a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A5 11052 bytes
SHA-256: d1bdcace2ac508f2677a219e6f67353f43a2411fc6064a895fe5122c0fbc2bb5
font_02_sfnt_off0000f271.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF271 16216 bytes
SHA-256: ccc5c5080cb828574fc6863bf2ad6597559f717425abdc8790e4776992c6926a