Malicious PDF — malware analysis report

Static analysis result for SHA-256 49e4b92a2b20d375…

MALICIOUS

PDF

83.3 KB Created: 2021-07-02 19:56:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7677ae7fb43b68a213d4f0f5f7699714 SHA-1: ef3e933fb85db474c109b1a9e8a757a5fcc3c5aa SHA-256: 49e4b92a2b20d375f124b7009e074769d7274de3168997a997e28af96e515088
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as 'Pdf.Phishing.Trojan'. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to other PDF files hosted on various domains, some of which appear to be compromised CMS uploads. The ML classifier also strongly indicated maliciousness. While no specific document body content was readable, the presence of these link farms suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://angkortaxiservice.com/userfiles/file/vitorasa.pdf
    • https://travelworld.ro/userfiles/file/xutefakuvujawe.pdf
    • http://tevukasveza.lt/ckfinder/userfiles/files/bazizalo.pdf
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/d6bb28cb36cb9bc23bc8d0c70b33e382/waduwetavomozib.pdf
    • http://ogbchurch.com/clients/880797/File/78212016975.pdf
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16075daf85c70e---39275049683.pdf
    • http://aksaxena.com/bpms/includes/fckeditor_uploads/userfiles/file/81471670895.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/ad4a4609e99885f7fd72a1fce63bfd8b/84749071029.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b0c13402085---rebosipef.pdf
    • http://conflictfreeelectronics.com/ourprojects/chowki/UserFiles/renuka/file/wekuvole.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16071793735410---5275632631.pdf
    • http://solyaris.pro/admin/ckfinder/userfiles/files/31983847063.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608220f04b09f---77503492901.pdf
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/9dc8589711bb1b26afd1c570ff135567/70158327243.pdf
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b78933dc817---79506889749.pdf
    • https://www.lightingsolutionsal.com/wp-content/plugins/super-forms/uploads/php/files/9547a0a0fc8c2046cc355f0aeb43d8db/pudukubob.pdf
    • http://szakkepzosiklos.hu/upload/file/vevaga.pdf
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/v5a0jom4ro6mdc5pveguvn1j92/50699161434.pdf
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4cbccbcc1---judasigizatejerawolumiz.pdf
    • http://iwish-cosmetics.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5d5918274---77507401716.pdf
    • https://wills.sg/wp-content/plugins/super-forms/uploads/php/files/59487312fc9946313790341f3197dd0c/10546624281.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=the+adverbs+of+frequency
    • 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_off0000e2c3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2C3 16792 bytes
font_01_sfnt_off0000fada.bin
0d99a6236d3647c27680a8e0aee8d6749ec2ac2a5316ae5e244e21deb2e92f60
pdf-font-stream PDF embedded font (sfnt) at offset 0xFADA 10868 bytes
font_02_sfnt_off000113b7.bin
8f391ff6563a9f6f8b7214858d5f57decceb560d32810f063c2802f36d7805f8
pdf-font-stream PDF embedded font (sfnt) at offset 0x113B7 17224 bytes