Malicious PDF — malware analysis report

Static analysis result for SHA-256 5d456f7560d448e9…

MALICIOUS

PDF

86.3 KB Created: 2021-09-18 17:24:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 74b58725a6038cfa7e1048ef5455cf7c SHA-1: 035af98aa3cc8499facfe4ea74ce2f02c3e655f1 SHA-256: 5d456f7560d448e94ef96795a36a2bd58a80858a4f008ce17382fc9620fbe3d1
156 Risk Score

Malware Insights

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

The PDF file contains a link farm with numerous URLs pointing to various websites, some of which are hosted on compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://idroter.org/userfiles/files/12467795956.pdf In PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/ragigumoxepim.pdfIn PDF document text
    • https://www.bountyvacation.com/wp-content/plugins/formcraft/file-upload/server/content/files/161365010f2296---23508609761.pdfIn PDF document text
    • http://merwepizza.com/upload/file/96882363476.pdfIn PDF document text
    • https://iasvn.org/Images_upload/files/bodovominal.pdfIn PDF document text
    • http://friulanapanini.com/images/file/netixibasix.pdfIn PDF document text
    • http://laibros.com/ckeditor/userfiles/files/3822767599.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1613615cde90ec---75015800216.pdfIn PDF document text
    • http://thriftstorewebsites.net/flash/thriftstorewebsites.net/file/puxujomovesogudabijet.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210916134915_gipl83.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144f8a61b8df---71720990492.pdfIn PDF document text
    • http://hindel-relax.ch/ckfinder/userfiles/files/buzefitamasom.pdfIn PDF document text
    • https://unitedfightalliance.com/ckfinder/userfiles/files/8001772886.pdfIn PDF document text
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/zijisufokobivulipu.pdfIn PDF document text
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/161327c7e7ec75---vazojenogoxasomo.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613eb07b0ea56---mupewod.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/89970247658.pdfIn PDF document text
    • https://cfi-registration.amyhalter.com/buzzboxgift/img/userfiles/files/kemesigogawopitu.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/xosigenejafijimesuziro.pdfIn PDF document text
    • http://reguitti-engineering.it/userfiles/files/zijawijalum.pdfIn PDF document text
    • http://dotacjedlaoze.pl/userfiles/file/97046342278.pdfIn PDF document text
    • http://gshosnab.ru/userfiles/file/32400692581.pdfIn PDF document text
    • https://officialbacknumber.com/editor_up/2663270814.pdfIn PDF document text
    • https://dichvuketoanvn.org/uploads/files/54905489464.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=which+country+population+is+highestPDF 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_off0000eb52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010364.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10364 18088 bytes
SHA-256: 2027589697c5a9591b8fd2f4716964eb6c8ea2f2abe48363c97666942447a0b4
font_02_sfnt_off000132c1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x132C1 10860 bytes
SHA-256: c62d0af65732945d293875cbbf7d9a53748a883424b9c1b85d9a270022ac826d