Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bc81805fdd4f845…

MALICIOUS

PDF

74.7 KB Created: 2021-09-06 15:03:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 27bd74ff71ab8330aaa4f3b85d7742d6 SHA-1: cc5a5d0041a171f4deb4dd773b56d8ea28f023b5 SHA-256: 6bc81805fdd4f8458a97671187a8642a208f291d59f66fff78d9c70280c9a049
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics as containing a link farm, with many URLs pointing to disposable hosting or compromised CMS uploads. The ML classifier and ClamAV also identified it as malicious, specifically as a phishing trojan. While no scripts were directly extracted, the presence of numerous external links suggests the document's primary purpose is to redirect the user to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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=categorization+worksheets+2nd+grade PDF link annotation
    • https://sport-jicin.cz/dokumenty/44256279690.pdfIn PDF document text
    • https://classconnbio.com/img-jacson/files/kepajivovoxefuxa.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/gigasituletagozadogelavok.pdfIn PDF document text
    • http://asqcert.net/files/files/99041792439.pdfIn PDF document text
    • https://cardion.dk/gfx/fckimages/file/99851048399.pdfIn PDF document text
    • http://isystem.hu/ckfinder/userfiles/files/mewowemesezutir.pdfIn PDF document text
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/l01vr73d0hps9qrptl853akuh0/59847486315.pdfIn PDF document text
    • https://prairieroseclothiers.com/FCKeditor/file/jeniderebimonufopijivi.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/022dcc2eeaf5d7feb13863179b7a1352/3409615916.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba845feeb62---85485409523.pdfIn PDF document text
    • http://faisaltowel.com/survey/userfiles/files/65347216437.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/us77qv5cjttsr4u4h8caneptv2/52822700667.pdfIn PDF document text
    • https://cualuoihoanmy.com/uploads/userfiles/file/85862865529.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/92718712173.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/u3u8kmesoee79tonbiffgeghu5/89409965405.pdfIn PDF document text
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/f91b877f6ae179408d34e098d8b57e8c/diguxatedipefavekojeremu.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b55c982465b---71481271452.pdfIn PDF document text
    • http://seritour.com/rsm/files/tesib.pdfIn PDF document text
    • http://mywayrtk.info/userfiles/file/pazuga.pdfIn PDF document text
    • http://opusbiz.kr/data/editor/file/482061764610dd7b9c1c03.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/80339380d3340cf595323808336c3904/bejajedinamilojiloz.pdfIn PDF document text
    • https://krzczonowice.pl/gfx/file/41595197704.pdfIn PDF document text
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/e31d9bd7bb93418de1935685bf3abe7a/48578836792.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a81335b1e97---nonoxarovasawiritonadu.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_off0000bee7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBEE7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d6f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6F9 18000 bytes
SHA-256: ad99c3767496eb5a001c2e686fc1d1002942cbb920d0b3cb6af7d0138d8d65f0
font_02_sfnt_off00010443.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10443 10872 bytes
SHA-256: a269c5d166488d2afa3f2c709f1e2592f515d2c4a4266329a5a7b49453e0cd33