Malicious PDF — malware analysis report

Static analysis result for SHA-256 31f746116d8b3387…

MALICIOUS

PDF

103.2 KB Created: 2021-08-20 22:45:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-23
MD5: ee6a39ac1378080f76694aa42d4886a1 SHA-1: 0fdac8c6065e871fb1618b59ec06bab57f90b3ca SHA-256: 31f746116d8b3387ec23e834e188265ad8813945297a21ec3ec634f900022f78
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

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 https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/b9dbf80bfe93163eabc51df624c5a788/ludivupirezilafawomevet.pdf In PDF document text
    • http://myafmc.com/clients/a/a5/a51d49d85de18111a3d718c63a5e5081/File/28381614760.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b4ff57e724b---lizizunadaluvoxisegera.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/32e53a164060fb4da24f5dec107f8c2f/dojunimelivizovaw.pdfIn PDF document text
    • http://pomodorolennep.de/gfx/userfiles/files/sasovojotavebex.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c85af1dfa6d---87877999859.pdfIn PDF document text
    • https://tradingphrases.net/userfiles/files/73700692583.pdfIn PDF document text
    • http://www.bufolari.com/public/immagini/file/12339549122.pdfIn PDF document text
    • http://shangrilayunnan.com/ckfinder/userfiles/files/87384874909.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/c35fa2eef293a48c5bb65375ed2d00a1/kanemelafinelerolez.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/522dd61f5631f6d802fad897694c7b9a/vopiwimurewupi.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607feb3f4bed3---10436701140.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16095254bb1253---95108237676.pdfIn PDF document text
    • https://rjiminfra.com/wp-content/plugins/super-forms/uploads/php/files/5ffb76615ce2d7797db6d17cc7b58dcb/tuwekop.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/3621e9767d59913b6b51430778bb725d/76367483090.pdfIn PDF document text
    • http://staropolski.net/Upload/file/webixuliponunoxemotip.pdfIn PDF document text
    • http://kardelendalgicpompa.com/uploadfiles/file/43746721916.pdfIn PDF document text
    • http://sourceandsecure.com/uploads/userfiles/file/5240582812.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b1a16759d3a---18672399574.pdfIn PDF document text
    • https://projetounificado.com/uploads/files/39862587284.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c83ada68b8---penebabafasolom.pdfIn PDF document text
    • http://garmagostaran.com/Upload/file/likuxijiwetogatemata.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b3465cc8af6---jadekavonobuzibo.pdfIn PDF document text
    • http://american-security-inc.com/assets/ckfinder/userfiles/files/92205332358.pdfIn PDF document text
    • http://brette-animation.com/userfiles/file/40569445429.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=instruction+cycle+in+computer+architecture+mcqPDF 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_off00012f0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F0D 10948 bytes
SHA-256: d9347b5df09aca2296dd8aba33cc4483213bfc03ce7df7bfb995a6d22b2f224d
font_01_sfnt_off0001484b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1484B 17516 bytes
SHA-256: dfd5a5c44f37717cff610c7a2f8398de51c73191be90c4eb7a2233696cf7bb27
font_02_sfnt_off00017627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17627 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1