Malicious PDF — malware analysis report

Static analysis result for SHA-256 55fe41ab5b58cf95…

MALICIOUS

PDF

65.1 KB Created: 2021-06-25 00:43:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-24
MD5: 101a09082c66005f5b8dcffa83546a26 SHA-1: 68512c089e0af30df597cd7b227bff92128f990e SHA-256: 55fe41ab5b58cf9573075988ecb3965509c9af5653d422247ecaacb12b9f3ec0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF document was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The document body, though heavily obfuscated, appears to be a lure related to 'electric potential difference worksheet answers', aiming to trick users into visiting these malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://skrabl.pl/www/rpbd/fck/file/jupapozunigamiwemaz.pdf In PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160cb2caf99f07---67650651999.pdfIn PDF document text
    • http://jshtextile.com/UserFiles/file/%5C/kexiverav.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/tiwumeb.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/07f146e69a26b0db7aa677787123e7b8/65447849724.pdfIn PDF document text
    • https://acryl-bg.com/userfiles/file/vanam.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/20210609/210609201456855149odm3gbdyl8o1.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/670501c939aeb3b10488d869b36ff63e/92018920361.pdfIn PDF document text
    • http://topcudental.com/img/userfiles/files/3371577853.pdfIn PDF document text
    • https://equator-maritime.com/userfiles/file/28484359692.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160862b4009269---96199892028.pdfIn PDF document text
    • http://arisutour.com/ckupload/files/16545466358.pdfIn PDF document text
    • http://broorybulldogs.com/clients/33993/File/kolen.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/911fea47dd9b9cf9fb434ffc68d6d162/duguku.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/zoravo.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/b343bb1a91f3216842a1f4f0bc2be6cc/kekud.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=electric+potential+difference+worksheet+answersPDF link annotation
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b24c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB24C 5144 bytes
SHA-256: f37aebcf96317758fb50ac66f0dc786da2c36a1bd49d1b37e7e9ee56cb4eab8a
font_01_sfnt_off0000c3cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3CC 10456 bytes
SHA-256: b01be62fad069c58e74195c252895df6b581ea4778dd91cdd76a18da1107019d
font_02_sfnt_off0000e716.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE716 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e