Malicious PDF — malware analysis report

Static analysis result for SHA-256 c28ed56971add3ec…

MALICIOUS

PDF

110.4 KB Created: 2021-09-05 13:47:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 54183f1395bde2b46adb6b81018869bc SHA-1: 97163d53bbd898c33d83255fa0745b6173bf76e8 SHA-256: c28ed56971add3ecef6f52aa6c74ba9660328c7aece364448b8de7d856a98e69
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of numerous URLs suggest the primary purpose is to manipulate search engine rankings or redirect users to potentially malicious content. ClamAV detection further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://gz-topstar.com/wp-content/plugins/super-forms/uploads/php/files/eee0eb7196def5299c0c287c50844eec/monuvolitaxasip.pdf
    • https://brillimet.com/uploads/files/202108281403512613.pdf
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/347e8ed68793faa73259fea53efb858b/riboditebuzalim.pdf
    • http://phone-server.com/userfiles/file/3975542554.pdf
    • https://sport-jicin.cz/dokumenty/22001763742.pdf
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160b833d4d5a60---nanusijasafexom.pdf
    • http://xn----9sbkvfu2aex3d.xn--p1ai/ckfinder/userfiles/files/tupadovuluxim.pdf
    • https://www.supremecaravans.com.au/application/third_party/ckfinder/userfiles/files/mofariworuto.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1612c8b0520410---xelube.pdf
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607c1c54313c9---67603379017.pdf
    • http://vce34.ru/attachments/file/fofofavezo.pdf
    • https://theemperorsoldclothes.co.uk/wp-content/plugins/super-forms/uploads/php/files/b5lmth11tf5jk3sogh6tic5nq8/returimibuduk.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/ab4d03520227f2815c7339fee1e47e75/vinekepabusiwanum.pdf
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160906959142af---xogikoxuvasalis.pdf
    • https://nguoixunghekiev.vn/userfiles/file/35593941738.pdf
    • https://afritransport.com/app/webroot/files/file/25630745521.pdf
    • http://pytextiles.com/userfiles/file/4022835804.pdf
    • https://cristalparkhotel.com.ve/ckfinder/userfiles/files/sazixukiregoxij.pdf
    • http://esthebel.de/userfiles/file/84420301897.pdf
    • https://www.akilciilacdernegi.com/ckfinder/userfiles/files/zitopizes.pdf
    • http://eqletstalk.com/uploads/files/202108271506493713.pdf
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/zemowesenuno.pdf
    • http://techscreening.com/userfiles/files/zufizegozurilerajuzurol.pdf
    • http://ajtoablakcentrum.com/_user/file/69943520185.pdf
    • http://espacioschillout.es/images/admin/file/21232713680.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=chronicles+from+the+future+pdf+complete
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001430a.bin
73492a5fe15dfc624e95738e9b7d8c18abed5c934234dc7f7b44951a4849809e
pdf-font-stream PDF embedded font (sfnt) at offset 0x1430A 21144 bytes
font_01_sfnt_off00017a0a.bin
1d6ed58d754ee74940228d332a316ea28dd04b81befe252a27561dcd55a97765
pdf-font-stream PDF embedded font (sfnt) at offset 0x17A0A 10856 bytes
font_02_sfnt_off000192e5.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x192E5 16792 bytes