Malicious PDF — malware analysis report

Static analysis result for SHA-256 afc11900cc83b8f3…

MALICIOUS

PDF

89.1 KB Created: 2021-08-31 23:08:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 41d9dc341d44f9599da25892491f9a79 SHA-1: d6cbb84ec938895202f6a58cf2bbfbf2803d3d73 SHA-256: afc11900cc83b8f358bbe1ab618c80312d00f485a0c51c33ef2b19f781c1354d
156 Risk Score

Malware Insights

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

The PDF file contains numerous external URIs and links to compromised CMS upload storage, indicating it functions as a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the presence of multiple suspicious URLs is the primary indicator of malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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=changing+earrings+after+6+weeks PDF link annotation
    • https://www.saltriot.com/wp-content/plugins/super-forms/uploads/php/files/506a25ad6faec48f4ac3c5f356cfac5f/47184128977.pdfIn PDF document text
    • http://stonebreaker.at/lokagekiserexo.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/0t88u5mcr7o1jou7ot9io3v6qg/wedimavexebe.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/406d3258d0e1ebe28cb77329e5740d5a/lemitasekimonutuzenakivi.pdfIn PDF document text
    • http://suncitygroup.ir/basefile/suncitygroupir/files/24591115468.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/ccc2b706d9119382c5a53cfb593ef874/99623721685.pdfIn PDF document text
    • http://manpukulivermore.com/uploads/files/megetikanuxisu.pdfIn PDF document text
    • http://fsoa.cn/userfiles/file/17424169443.pdfIn PDF document text
    • https://vieclamxaydung24h.com/upload/files/93011891057.pdfIn PDF document text
    • https://goactive.hu/wp-content/plugins/super-forms/uploads/php/files/6189a1e6620b92738f4f62afe7255a2f/bipidolodijefinibaminujol.pdfIn PDF document text
    • http://yar-net.ru/userfiles/file/pudibolalaxesasimi.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070de24277ad---2150645095.pdfIn PDF document text
    • http://artdealer.vn/upload/fckimagesfile/3fe7dee04e398c6a7d5bd45311acb2da.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/g7u2t4l4bd5q0fb1rm3r5r81nn/dobunoki.pdfIn PDF document text
    • http://nedirajtebosnu.net/userfiles/file/zomubofazomariwuxiveno.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ac57708ad6---kelukazitepopepuzatuf.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/f93426ba418d92e37f52be29d1f0071b/jesanifoxitirawu.pdfIn PDF document text
    • http://stellarvvv.ru/ckfinder/userfiles/files/32595005059.pdfIn PDF document text
    • https://rivaflo-south.in/userfiles/files/12902894078.pdfIn PDF document text
    • http://yuhongzg.com/d/files/17486760143.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_off0000f29d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF29D 19016 bytes
SHA-256: 7416f80b4b410cc2592481e6a6ba5b4f1a7ba40f77f53dc12c932c73f2ab5273
font_01_sfnt_off0001246d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1246D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013c84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C84 10704 bytes
SHA-256: 353c7eaed573c48deee9d37e770677e7310c0e3c3284531f1e6e5361ad487f44