Malicious PDF — malware analysis report

Static analysis result for SHA-256 0639c61083c3060d…

MALICIOUS

PDF

76.9 KB Created: 2021-06-24 05:11:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: c5887f0ec849bca48db44a499f28d605 SHA-1: f66b0fa527d8edb96c255e4cd74b122989d9384f SHA-256: 0639c61083c3060d647c7ab1b8a8f976b969fc861377766c173e4030c8d68a5e
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it functions as a link farm. The embedded links point to compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The document body, though heavily obfuscated, contains text related to 'army cyber security fundamentals', likely a lure to entice clicks on the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c13bfdee307---lanevidirusexilonalokoreg.pdf In PDF document text
    • https://sunrise-photon.com/upfiles/editor/files/penerapi.pdfIn PDF document text
    • http://zatacorp.com/upload/files/betuzuvaxen.pdfIn PDF document text
    • http://coffee33.ru/archive/file/70020194460.pdfIn PDF document text
    • https://englewoodgrassfarm.com/wp-content/plugins/super-forms/uploads/php/files/02ee13ba60e73c81c4139ae21304862b/36275556892.pdfIn PDF document text
    • http://willbramephotography.com/40193993869.pdfIn PDF document text
    • http://woonhuislift.info/wp-content/plugins/formcraft/file-upload/server/content/files/16072d02996ff1---93520504755.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ad2a1710797---ramazerewa.pdfIn PDF document text
    • http://wchs65.org/clients/b/bb/bb65574a37642f7fe3135935df861e67/File/fodifawupisuda.pdfIn PDF document text
    • https://ehotelgateway.com/bot/ckfinder/uf/files/roteburiwasipax.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/8103f04e90ae5973213209314c5d23cc/kosoxanuzokomazu.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/16076068416f68---luvofupugejenigo.pdfIn PDF document text
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/5fbeda8c4f1749e06fdb022f2ada4c45/kemalikuluwapefirilalepu.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b87a899b253---87681102092.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f77d0a6a3a---57309818911.pdfIn PDF document text
    • https://cam-ceeds.org/ckfinder/userfiles/files/kitisoxij.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=army+cyber+security+fundamentals+2020+exam+answersPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ddea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEA 5604 bytes
SHA-256: 38d67d6149f084363166405999bd885f3fc42ad5c6c15a0c440eebe9b21d4db2
font_01_sfnt_off0000f0f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F7 11464 bytes
SHA-256: 0f5ff737919df3c5a264d722189806ad8e86a9212d7c22e203f402eb50af5dec
font_02_sfnt_off000117fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117FC 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176