Malicious PDF — malware analysis report

Static analysis result for SHA-256 de7c1bc3f8d51188…

MALICIOUS

PDF

71.8 KB Created: 2021-09-05 19:25:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 540f376905dae4979bd5c9f3e0682cf0 SHA-1: 1636ddb655bbd0008d6ac4700287f2877ba1c2df SHA-256: de7c1bc3f8d5118881927d005dc5a5c3d6cd35f1ba8053f2264fd216464186b5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a phishing or malware distribution scheme. The presence of external URIs and link farms points towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nomylo.ru/uplcv?utm_term=nutone+range+hood+installation+manual PDF link annotation
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/t730eqpouplb7d6vkeheh3lgm0/82426996284.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161321d07a717a---nukaz.pdfIn PDF document text
    • http://for-rent-aalst.com/wp-content/plugins/formcraft/file-upload/server/content/files/160760dd81ba21---kojidat.pdfIn PDF document text
    • http://mbfeed.vn/upload/files/sipuze.pdfIn PDF document text
    • http://pokewaveanaheim.com/uploads/files/15854260120.pdfIn PDF document text
    • https://afmiletisim.com/resimler/files/tizevibezonazogopemoserow.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd60767d31e---63369547888.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021082614160373499.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c69c6f46669---linuj.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc026d72367---wetepumozepidupi.pdfIn PDF document text
    • https://lawina-radom.pl/files/file/zixogasesegikeg.pdfIn PDF document text
    • http://prochem.vn/images/uploads/files/5526359523.pdfIn PDF document text
    • http://careerdynamic.com/clients/3/3d/3d9dba0a3645e5854abf1db7654b9c86/File/60221519847.pdfIn PDF document text
    • https://olterus.com/contents//files/59778859001.pdfIn PDF document text
    • https://imagebuzz.net/ckfinder/userfiles/files/68751595433.pdfIn PDF document text
    • http://ratchadatitan.com/UserFiles/File/nubogipi.pdfIn PDF document text
    • https://sedefartphotography.com/resimler/files/bifelapugomi.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c895fd8c5f---simitifujurob.pdfIn PDF document text
    • http://blpest.com/UserFiles/file/50798060497.pdfIn PDF document text
    • https://immo-macedo.lu/userfiles/files/52917188919.pdfIn PDF document text
    • http://panziofabian.hu/fck_kepek/vitipobekumalogeziw.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/78d5ec370ed0fead6f3248d49fa6d4f4/256838929.pdfIn PDF document text
    • 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_off0000b6cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cedd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEDD 16516 bytes
SHA-256: b9515a1ba6a4d47da65773cefd1e150fcf3429f7495ef149849161133419d6fa
font_02_sfnt_off0000f965.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF965 10772 bytes
SHA-256: 139f2f610ff1aae5883f1dbf0803df958bf55b4d75fc2025456b7068a13e07e4