Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1f2b4498c34a910…

MALICIOUS

PDF

87.6 KB Created: 2021-09-09 19:47:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: ab17ca94caaf40ea3660431f5d981b2c SHA-1: 2479caf13ebde460c1a20ecdabd8b5e63be544d3 SHA-256: b1f2b4498c34a9109271b3f5a253679adec1055e6584d475e99775f036371f9d
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by a machine learning classifier and ClamAV, which flagged it as a phishing trojan. The file functions as a link farm, containing numerous URLs that point to external resources, including a link farm hosted on a compromised WordPress upload directory. The presence of multiple external links suggests an attempt to redirect users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://nakipoglugroup.com/upload/ckfinder/files/57680526357.pdf In PDF document text
    • http://phoiinnhiet.com/images/uploads/files/98458002281.pdfIn PDF document text
    • http://yusungchart.com/userData/board/file/57664627501.pdfIn PDF document text
    • http://mebel-moscow.com/content/xuploadimages/file/68455017043.pdfIn PDF document text
    • http://mictrogiang.com/userfiles/files/makagobogapelaxebi.pdfIn PDF document text
    • http://hauptlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/64506562955.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/74035788807.pdfIn PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/161390dbe08cb7---figaluxegitazepojokap.pdfIn PDF document text
    • http://studioprogettoarchitettura.eu/userfiles/files/kagopi.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/40791256660.pdfIn PDF document text
    • http://htwy.com/upload/file/zirukowozefezozuf.pdfIn PDF document text
    • http://good163.cn/Uploadfiles/files/kigafavedavejalagajib.pdfIn PDF document text
    • https://smg.bid/ckfinder_userfiles/files/wusenofozufoladarulawav.pdfIn PDF document text
    • https://goacetours.com/ckfinder/userfiles/files/sikuxugajuximobitiwupex.pdfIn PDF document text
    • https://euroquimicadistribucion.com/zabaleta/data/imagenes_contenidos/file/12872968214.pdfIn PDF document text
    • http://cn-biyoute.com/d/files/pexikagozoni.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16138df2177f78---kanolenogozavi.pdfIn PDF document text
    • http://thoitranglani.com/upload/files/59043092896.pdfIn PDF document text
    • http://monteconsultants.com/image/upload/File/54505272671.pdfIn PDF document text
    • https://ms02bet.com/contents/files/27694889656.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130f5792acec---77701776623.pdfIn PDF document text
    • http://top-caster.com/userfiles/file/20820637824.pdfIn PDF document text
    • http://kubablimel.pl/Image/files/6327230775.pdfIn PDF document text
    • http://worldplastsolution.com/ckfinder/userfiles/files/58773511698.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=rs+slayer+mastersPDF 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_off0000f511.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF511 10112 bytes
SHA-256: 30554fd7d88fd462d5bf883dd31620ecc25c6ce46e0fcaf9837c50da358d25ce
font_01_sfnt_off00010bbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BBC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000123ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123CE 17500 bytes
SHA-256: ed722ef7db796c5d9c9be2bff742887965bf5df9299648a4011f9d373f869406