Malicious PDF — malware analysis report

Static analysis result for SHA-256 6af31a9bca52a0f0…

MALICIOUS

PDF

81.0 KB Created: 2021-09-02 15:28:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d2d2b52bbc1fa74e88c9e9ef0e18ad81 SHA-1: b7baea6231d950b5864aa1bcdcd52b3395ab7ecf SHA-256: 6af31a9bca52a0f0914245877e1931b58bd3a0b2564dad7eb7059bb60df77062
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://kalmi.ru/upfiles/files/wenuxexozufozeloni.pdf In PDF document text
    • https://nikosdimos.gr/userfiles/file/54960482506.pdfIn PDF document text
    • https://centaur.vri.cz/docs/files/56746641724.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/da896c1bea552167ab78afa69a85e623/3693929773.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/acbc12d4d0b992d9b81ae21c53672af1/78130873307.pdfIn PDF document text
    • http://pharmorgsyn.com/upload/files/80222206771.pdfIn PDF document text
    • https://www.finestkindcharter.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad84b60a96b---kumejotitik.pdfIn PDF document text
    • http://mea-travel.pl/userfiles/file/96678984260.pdfIn PDF document text
    • http://cycling-software.com/files/file/81956820184.pdfIn PDF document text
    • http://matkinhantai.com/luutru/files/voderurikolopumu.pdfIn PDF document text
    • http://rauvuonsach.net/images/uploads/files/58532800240.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/95914965407.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/83e5c61bdc23ffb7ea14b2ba364015d9/gidodipevivajoxixoxeweb.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/43255844880.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160876e6d02e82---rixevu.pdfIn PDF document text
    • http://stasta.com/userfiles/file/2994945068.pdfIn PDF document text
    • https://besteva.com/upload/files/kiziwuganigilofadoweloxa.pdfIn PDF document text
    • http://lustigersteirer.at/userfiles/file/xerirojaz.pdfIn PDF document text
    • http://cosmikkino.ru/sadm_files/dubudojapovowuginowadilud.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161210e6075106---98232812791.pdfIn PDF document text
    • http://jnnycc.org/userfiles/file/2017371300.pdfIn PDF document text
    • http://sanarina.de/ckfinder/userfiles/files/56400463998.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=sample+scientific+research+paper+pdfPDF 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_off0000d5b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5B6 18464 bytes
SHA-256: 7c38cea2ff872eeb7915124f41a96e97c9557c58a6169ece6c31be415f722a6c
font_01_sfnt_off00010589.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10589 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011da0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA0 10840 bytes
SHA-256: 705a4164eeb494a2a598b528079ace07350e82028788130569b23da7918caa61