Malicious PDF — malware analysis report

Static analysis result for SHA-256 ffe8b24c7b0858c3…

MALICIOUS

PDF

73.2 KB Created: 2021-09-27 05:55:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 236fd4d85f45ed20d4ea49c42524347c SHA-1: c26ddb87abd158e700f4e62d4ec89437e8e7ef47 SHA-256: ffe8b24c7b0858c3c6e83ef8fe25680bc4b200edf3aaf5cd3fdc46f166d2a5a0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics indicate the document functions as a link farm, directing users to compromised WordPress upload storage and other potentially malicious sites. The embedded URLs and the nature of the heuristics suggest an attempt to deliver phishing content or a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9940

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://vivatbacchus.hu/files/file/49837711904.pdf In PDF document text
    • http://svb-volleyball.de/userfiles/file/49425233484.pdfIn PDF document text
    • https://braindevelopmentmaps-org.neurondevelopment.org/userfiles/files/86945332148.pdfIn PDF document text
    • https://snowcat.pl/admin/ckfinder/userfiles/files/50849302242.pdfIn PDF document text
    • https://odlingfamily.com/userfiles/file/13408085477.pdfIn PDF document text
    • https://ud-hobby.com/images/Upload/file/48951827129.pdfIn PDF document text
    • http://sheilahancock.net/blogfck/file/56523001642.pdfIn PDF document text
    • http://leeclinic.kr/userData/board/file/67668116233.pdfIn PDF document text
    • https://nepoo.ro/app/webroot/files/userfiles/files/duwefuwasuwegukage.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/90280858289.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1614c62008c2ef---51571412312.pdfIn PDF document text
    • https://cfbadalona.net/ckdata/files/96100818210.pdfIn PDF document text
    • http://bjyhyy.cn/filespath/files/20210921064920.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/htgg8q8o75c368r8mktshpq048/xexafovezumeru.pdfIn PDF document text
    • http://ryanoomen.nl/uploadimages/files/navovajebu.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614cc5791a280---ziwuzewodovawu.pdfIn PDF document text
    • http://prepearl.com/uploadsfile/60144904101.pdfIn PDF document text
    • http://sandiego.songhakbbq.com/uploads/files/fufur.pdfIn PDF document text
    • http://mopron.ru/upload/files/bolemoxobubopijosorazorom.pdfIn PDF document text
    • https://mongolia-volkslift.com/uploads/files/miwopel.pdfIn PDF document text
    • https://lacaune.hu/userfiles/file/28650586114.pdfIn PDF document text
    • http://christopherdallo.com/file/sifenibevotojaj.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/bokisasezowitepeputubota.pdfIn PDF document text
    • http://giasuthanhdat.vn/Images_upload/files/pegik.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613575dfecdc4---winikew.pdfIn PDF document text
    • https://drnanemilk.com/tctt/sites/aaa/file/gebis.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=android+app+for+photo+editingPDF 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://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_off0000b723.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB723 18428 bytes
SHA-256: 9f143500b0c63ddcd3b129177ee4835b04a300ca706ccee9b049245179c483c8
font_01_sfnt_off0000e72d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE72D 10544 bytes
SHA-256: b16098e455494672df772338bb60ea8e6a2a74b68f5ed75bc711f70fe8cab979
font_02_sfnt_off0000fee9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEE9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1