Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c38283de4051a6…

MALICIOUS

PDF

78.7 KB Created: 2021-07-24 04:52:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1a29812f4e0166f75cb0d862e4a873e0 SHA-1: 0ef10e1a942069fab300e2828fd9768899b6ceaa SHA-256: 31c38283de4051a6f124f50966eb1f91ac3f49df5a02e6f9ab10f71a9f4f94f2
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to a compromised WordPress site, identified by heuristics as a 'link farm on disposable hosting'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure suggests the document's primary purpose is to redirect users to malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608dad906ad9e---82585080116.pdf
    • https://heritagecambodiatravel.com/userfiles/file/mefawewimuvesogoxadowetat.pdf
    • https://www.davidcosz.de/wp-content/plugins/super-forms/uploads/php/files/tvcnpul3tc6fi8uuq6toqht2dr/duforesajetimuwar.pdf
    • http://www.rotudavid.com/ckfinder/userfiles/files/durilemunovasa.pdf
    • https://baxsporthorses.com/userfiles/file/25341688551.pdf
    • https://www.xyoaa.org/sites/default/files/files/46307104515.pdf
    • http://meadescafe.com/userfiles/file/nuwosepuvukijexuti.pdf
    • https://adsbudget.net/userfiles/file/fuviv.pdf
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/f4qrpqe6uk99vut7urenq3rdmm/kejedoxamosepesagifi.pdf
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607664f251525---tivitonenadibubabozipu.pdf
    • http://mamnonsaokhue.vn/app/webroot/files/ckfinder/files/winogonigifogoz.pdf
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160987e390fbd6---73539666948.pdf
    • https://cleaner.pl/userfiles/file/demitilazoliwotip.pdf
    • http://www.temaricerca.com/entry2013new/admindia/ckfinder/userfiles/files/40806712998.pdf
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/kjvrk5hafee5o73ue03i571lb7/55935381711.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf7fcf0f6f1---35172605983.pdf
    • http://neuragen.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b772b89acd7---dexixumowomawuzugemef.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a3880060549---vukomujajodisodap.pdf
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160f0d6aa9b4d6---xerabopakivofo.pdf
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/ce1d9dcec0a0c02018012c27f8f67f4a/12661080445.pdf
    • https://paron-rebondir.com/uploads/files/texelaxapojezajuwu.pdf
    • https://www.chortho.co.uk/wp-content/plugins/super-forms/uploads/php/files/f60bnrehg4r3fm9vdnqmbtj8sk/lafexumuroriporasin.pdf
    • https://afayl.com/userfiles/file/56691388792.pdf
    • http://://www.cdc.gov/nczved/divisions/dfbmd/diseases/typhoid_fever/
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=salmonella+typhi+o+1%2F80+artinya
    • 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_off0000cf4f.bin
e2c53a4200dc10f8b12f6e68c0e9dfc0af6f502e7f8b708dfb3d18dcf6e47044
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF4F 16964 bytes
font_01_sfnt_off0000fbd7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD7 16792 bytes
font_02_sfnt_off000113ee.bin
526b582cefde04e61b8c0ba9b2317334aa69ba5d9302105a99065f7ae90d6a27
pdf-font-stream PDF embedded font (sfnt) at offset 0x113EE 10952 bytes