Malicious PDF — malware analysis report

Static analysis result for SHA-256 5db559485f825ae1…

MALICIOUS

PDF

83.1 KB Created: 2021-06-05 11:51:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-01
MD5: 0bfb57804c3ed3138a5e35bbb3549fed SHA-1: 877995c6ba1f42e40debb8b4da6e14f5e0e184e9 SHA-256: 5db559485f825ae131605854d441e4f072b1f8a8e55f882085728404c32ff450
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://inwebjor.ru/uplcv?utm_term=sonic+boll+skins+mario PDF link annotation
    • http://indel.sk/userfiles/file/bevuxesuxebakiwejeritezul.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/e6231bc38303863bd59d864cb06e9629/pafavojif.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/tm5t9acpb7tcbk4e5p9ufk3n39/pexikosofuwuxoxivibunivo.pdfIn PDF document text
    • https://www.makathastaliklari.net/wp-content/plugins/formcraft/file-upload/server/content/files/16080c83582a6f---besurowav.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160baaa4ec85b4---72763416607.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092890c27d4f---76896819420.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609121dddaeaf---xozelagikeve.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080fae794772---74259943387.pdfIn PDF document text
    • http://activesolutionelectric.com/images/file/4505643885.pdfIn PDF document text
    • https://prosaison.fr/userfiles/files/nakorabirizenudatibuliva.pdfIn PDF document text
    • https://skyfireconsulting.com/wp-content/plugins/super-forms/uploads/php/files/parj687ukri98kjv4u4628gi4f/sutek.pdfIn PDF document text
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/1eeisqd3penl07nhvjdgsfv3mh/subogotewo.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f4850bb8e6---43270793660.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b453549859a---72657277178.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000ef10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF10 5252 bytes
SHA-256: f8a45322ee0387c540af751c8ba30745940c0e00c78923035528d1947235f2cb
font_01_sfnt_off000100d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100D8 12760 bytes
SHA-256: 79c66bf2d4c09abe0af86c2bbbc9b4d16c3a94dbcf9a3e96ee46ba0fa95801f4
font_02_sfnt_off000128ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128EE 16196 bytes
SHA-256: ed614ff3ac2e387b3dffe3adc8533a73dd514e171fc201cb60d70b5b5a32e0ff