Malicious PDF — malware analysis report

Static analysis result for SHA-256 af98cb522f55d10e…

MALICIOUS

PDF

124.4 KB Created: 2021-10-15 09:01:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 165d4da78d6a2fc2dd4d5e6de7022b59 SHA-1: b8b65ae21ee312a9095f88457e659fbe670f6a01 SHA-256: af98cb522f55d10edeb958c45ae92399729c06c0a0eb87c1f0f9a28c11c37903
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of embedded URLs, many of which point to compromised websites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the nature of the heuristics strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://alconsprom.ru/ckfinder/userfiles/files/21520163588.pdf In PDF document text
    • https://habibitours.com/ckfinder/userfiles/files/11462548939.pdfIn PDF document text
    • http://huichem.com/ckfinder/userfiles/files/kematubazatero.pdfIn PDF document text
    • https://raghuvirtrading.com/userfiles/file/87273967118.pdfIn PDF document text
    • https://wecareprogram.org/images/file/sowiwilimesagad.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/b58772accd5bae7cf495f06e0258f1a4/85144163797.pdfIn PDF document text
    • http://zerosquareonline.com/file/sodede.pdfIn PDF document text
    • http://valdhans.cz/userfiles/file/18844282337.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/161363403368b4---popatanasofawuvav.pdfIn PDF document text
    • http://prograsifkalip.com/files/loxuvuviripesiwekowifi.pdfIn PDF document text
    • http://permanentnimakeup-brno.cz/userfiles/files/goxejavi.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/27844611851.pdfIn PDF document text
    • https://www.bandungpilotacademy.com/file/74239436372.pdfIn PDF document text
    • http://lasfyy.com/uploadfile/file/20210928191032751.pdfIn PDF document text
    • http://novelinternationalschool.com/ckfinder/userfiles/files/23351717389.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/99218518278.pdfIn PDF document text
    • https://olterus.com/contents/files/96781534371.pdfIn PDF document text
    • https://ienter.bg/files/wabepupaj.pdfIn PDF document text
    • http://sntaviator.ru/ckfinder/userfiles/files/9127268976.pdfIn PDF document text
    • http://didaconcept.com/admin/fckeditor/file/vurejowofixepezixifu.pdfIn PDF document text
    • http://connectcontrol.net/files/userfiles/files/lolodokefusatokiratukaf.pdfIn PDF document text
    • https://cissud.it/uploads/ck_editor/files/50210119399.pdfIn PDF document text
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1614b3c708e492---xebawuxawomaduzupum.pdfIn PDF document text
    • http://wgadget.com/file_media/file_image/file/38076908727.pdfIn PDF document text
    • http://feedproxy.google.com/~r/Xvkpad/~3/tgwjJlsMqHc/uplcv?utm_term=please+have+a+glancePDF 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_off000186f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x186F4 18156 bytes
SHA-256: 4d54b662fb1e839f32c9a2ba4db94582a6e814027ae1d3eb0064ec2af72d767d
font_01_sfnt_off0001b528.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B528 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001cd3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CD3F 10168 bytes
SHA-256: 8333d9f91e828038fc7e42a4889c46bd91183459010b6fecca9db838f7191c7c