Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ae31cf5ffcdd2ed…

MALICIOUS

PDF

84.4 KB Created: 2021-09-12 15:13:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: eb322acafc23cea82dca0bc5c613b7b8 SHA-1: ddf7dc89c8053c2fb47c1d8dd2d509c375ab0086 SHA-256: 1ae31cf5ffcdd2ed4521faad6b968482f4e7d0eda965b8ba60737e15f828cab0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, with numerous embedded URLs. The document body is heavily obfuscated and contains no readable text, suggesting its primary purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://allytemp.ru/uplcv?utm_term=cydia+android+emulator PDF link annotation
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161357c0f5d863---52844692545.pdfIn PDF document text
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16137791272133---64947464762.pdfIn PDF document text
    • http://fitnessklub-impuls.pl/uploads/assets/file/31447728410.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/48535815402.pdfIn PDF document text
    • http://architettoletiziamasciotta.eu/userfiles/files/peluneloguwidakeso.pdfIn PDF document text
    • http://zonazero.es/userfiles/file/46967317453.pdfIn PDF document text
    • http://www.biogreeno.com/cms/ckfinder/userfiles/files/revikekonabefur.pdfIn PDF document text
    • https://banghenails.com/upload/file/jerigopawegatovumapefiki.pdfIn PDF document text
    • http://e-junghan.com/userData/board/file/giwalededogetiwetuxi.pdfIn PDF document text
    • http://viettranslators.com/webroot/img/files/zunobelexirinukedawukiri.pdfIn PDF document text
    • https://foodthings.us/userfiles/file/joxemi.pdfIn PDF document text
    • http://okna-dvere-online.cz/media/upload/upload/file/65213778161.pdfIn PDF document text
    • http://hitelesen.com/userfiles/file/kufumisiwewu.pdfIn PDF document text
    • http://formel1vermietung.de/userfiles/file/81416376001.pdfIn PDF document text
    • http://funkyspa.net/ckfinder/userfiles/files/21124387599.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/29864989599.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/wuwewumeromobeluxu.pdfIn PDF document text
    • http://myrbacken.se/login/ckfinder/userfiles/files/15224133203.pdfIn PDF document text
    • https://el-tall.pl/pics/file/59390444631.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b2f60388c9---xogozabetujufunopeze.pdfIn PDF document text
    • http://www.srijonihealinghome.com/fckimages/file/32812840238.pdfIn PDF document text
    • http://ac-kenigsberg.ru/files/file/10464384029.pdfIn PDF document text
    • http://at2apigroup3.com/contents/files/83536687386.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_off0000e5c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C0 10484 bytes
SHA-256: cbd84fdb66539523b53ebd06a2d570ebb7af21d0356a334db32f19448a38712e
font_01_sfnt_off0000fd8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD8F 17948 bytes
SHA-256: d0e08da35fb5d7f3108cb138e7ec7abedff6ca5f01ec1646c49c6513291506f2
font_02_sfnt_off00012c18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1