Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3f911ddb7abe439…

MALICIOUS

PDF

79.4 KB Created: 2021-09-13 00:57:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 085a69cfa0b2a765fe2943782697646f SHA-1: facd9ef3629953862f37ac1a9aeb5c808289b732 SHA-256: b3f911ddb7abe439e82565b2d7f97e45faf1bc328e76be64316091546fbc827d
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to websites hosted on compromised CMS upload storage, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://greensketch.in/userfiles/file/81698396398.pdf In PDF document text
    • https://himalayanwanderer.com/himalayan/userfiles/files/dizosej.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136731e99676---lumetivewosamezodumo.pdfIn PDF document text
    • https://kimcert.com/E/file/49277062863.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.com/ckfinder/userfiles/files/70392338207.pdfIn PDF document text
    • https://episcopiaoradiei.ro/files/37333064494.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/bimevepelopeninabopi.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/048461a4a78a000fe319d67988fb8b35/xonijez.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ce0a33b84---mazizumazadi.pdfIn PDF document text
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f2d3301cab---87378512895.pdfIn PDF document text
    • http://rotang.net/userfiles/file/57056730646.pdfIn PDF document text
    • http://vino-charlie.cz/userfiles/file/zojarabinifiguforizomeb.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/lokomo.pdfIn PDF document text
    • https://renfrewareahealthvillage.ca/ckfinder/userfiles/files/betebopuxonosu.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1612fce5cefdcd---42893782350.pdfIn PDF document text
    • https://inunekocp.jp/mailmagazine/upload/files/sesarirufaj.pdfIn PDF document text
    • http://hotelpenza58.ru/ckfinder/userfiles/files/57105977554.pdfIn PDF document text
    • https://strings97.hu/userfiles/file/4512372321.pdfIn PDF document text
    • http://servicedental.it/userfiles/files/damepibimolesapow.pdfIn PDF document text
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132b456734aa---saxonu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=where+are+prokaryotic+and+eukaryotic+cells+foundPDF 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_off0000d13b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD13B 17296 bytes
SHA-256: 109bffb3b5f4bb24539cb6bf8916ee2324f0e6858ef1eb5097a644d002941c99
font_01_sfnt_off0000fe03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE03 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001161a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1161A 11016 bytes
SHA-256: fb2c0f9bea657b238066396d99e40d8bef44027013921d7aae200c4908141fab