Malicious PDF — malware analysis report

Static analysis result for SHA-256 525eace83332859e…

MALICIOUS

PDF

74.0 KB Created: 2021-09-15 17:58:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d3103c03abaaa8a46ddeebc6cab80764 SHA-1: 1b9aaa04228eb11faf82f962a2c5a880247c00fe SHA-256: 525eace83332859e40d4e5919a3f1e67a7b3986ba1b69c9d9850930b4252876e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, with several pointing to compromised WordPress sites and other potentially disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or directing users to malicious content. The presence of link farms on compromised CMS uploads suggests an attempt to leverage legitimate but compromised infrastructure for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://marchmont.ru/imgs/file/19415659459.pdf In PDF document text
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613311ab0e433---jebamuxodiwajilu.pdfIn PDF document text
    • http://mlight.cz/archiv/file/rovewuke.pdfIn PDF document text
    • https://comfortinnbarrie.com/phpsites/vertical_living/uploads/file/76161138921.pdfIn PDF document text
    • http://acupunctuuryao.nl/ckfinder/userfiles/files/46791433986.pdfIn PDF document text
    • https://fullprotec.com/ckfinder/userfiles/files/97819464145.pdfIn PDF document text
    • http://hotechike.com/files/files/tigove.pdfIn PDF document text
    • http://chinawin-consult.com/userfiles/65798986071.pdfIn PDF document text
    • http://salt17.com/userfiles/files/jirupofokor.pdfIn PDF document text
    • http://decorstore.eu/upload/file/lojuronokekagadodowukawut.pdfIn PDF document text
    • http://e-restauracion.com/app/webroot/files/uploads/files/84779340126.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ecfa3496ee---dulebagazejegudetiju.pdfIn PDF document text
    • http://candleelectricals.com/uploaded_files/userfiles/files/19207234355.pdfIn PDF document text
    • https://ctners.com/ckfinder/userfiles/files/38115300743.pdfIn PDF document text
    • https://lostfoundglobal.com/userfiles/file/53991144108.pdfIn PDF document text
    • https://adproissy.emailingmanager.com/uploads/editor/file/numajugopan.pdfIn PDF document text
    • https://wsbtitan.com/images/file/85835547226.pdfIn PDF document text
    • http://anquocrealty.com/uploads/image/files/gujefemezigo.pdfIn PDF document text
    • http://purofirstli.net/userfiles/file/zufabav.pdfIn PDF document text
    • http://konberdbio.com/upload/files/laxuxapopudi.pdfIn PDF document text
    • https://llibreriaha.com/img/events/file/jerezuwewak.pdfIn PDF document text
    • http://progettogeometra.it/userfiles/files/68934751357.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/55d2b736c33ab313e90ddfaa886fd2fc/getufagap.pdfIn PDF document text
    • http://telecycling.org/files/file/tatiwirovegiduse.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=tanix+tx3+max+firmware+android+9PDF 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_off0000bce8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d4ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4FF 10792 bytes
SHA-256: 52e87df2250fa8b7181450aefdb3312e59970629779ecde98b0c3103d341d258
font_02_sfnt_off0000edf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDF4 17300 bytes
SHA-256: 2bb59f63b15470cbd8d85648f04fba9a2541c024ec084685ed8b09740cecc2e0