Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b9fec1ece302dc5…

MALICIOUS

PDF

78.3 KB Created: 2021-09-12 13:00:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 80e4eca2858302116d9442e00b11c9af SHA-1: 074f6c5ce91e3ded4a2d57a3135a5900e6604786 SHA-256: 2b9fec1ece302dc5332f7590344e410c5dec5a03aa2d21b09343090bc1741596
156 Risk Score

Malware Insights

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

The file is identified as malicious by a ML classifier and ClamAV, with the latter specifically flagging it as 'Pdf.Phishing.Trojan'. Heuristics indicate the PDF functions as a link farm, containing numerous external URIs and pointing to compromised WordPress upload storage. The presence of multiple links and the nature of the detected threat suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://cructi.ru/uplcv?utm_term=offline+google+t%C3%A9rk%C3%A9p+android PDF link annotation
    • http://tinhdauvietnam.vn/upload/files/98905614023.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/bosiwepupimafaj.pdfIn PDF document text
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/16136c0415f915---34272952554.pdfIn PDF document text
    • http://srtprogetti.eu/userfiles/files/22924297228.pdfIn PDF document text
    • http://moscreen.in/cmsfiles/file/3062528335.pdfIn PDF document text
    • https://coachtourbusrental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137cfdb20406---gokotoguzexuvujuwu.pdfIn PDF document text
    • https://groupburuemas1.com/contents/files/tivanewatidem.pdfIn PDF document text
    • https://avukatwebsitesi.kocgrafik.net/upload/files/74377489695.pdfIn PDF document text
    • https://groupunsur1.com/contents/files/divarifu.pdfIn PDF document text
    • https://hw-power.com/uploads/ckfiles/files/6138127418d63.pdfIn PDF document text
    • https://prawobrzeze.info/userfiles/file/71693455549.pdfIn PDF document text
    • http://asfalon.com/__files/file/vevetozopuxetetaguj.pdfIn PDF document text
    • http://abwva.com/uploads/files/nikawuxiponuponug.pdfIn PDF document text
    • https://rivieresoceanie.com/userfiles/file/sokowosijelerope.pdfIn PDF document text
    • https://vinatech.com/userfiles/file/povelefaw.pdfIn PDF document text
    • http://renknh.com/ckupload/files/getusefixexavoluzimexulip.pdfIn PDF document text
    • https://implantsdentairesdesmoulins.com/upload/editor/file/maralitazewilojefudo.pdfIn PDF document text
    • http://styrexon.cz/userfiles/file/biluwefudaz.pdfIn PDF document text
    • http://www.casasemio.com.br/ckfinder/userfiles/files/nasimurujegenezuponof.pdfIn PDF document text
    • http://icaalliance.org/filespath/files/20210903100225.pdfIn PDF document text
    • http://teakdeck.pl/files/file/dobawukagi.pdfIn PDF document text
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/a22da73a75c98a6f79adc8823d89446e/85092544954.pdfIn PDF document text
    • http://hsi-international.com/ckfinder/userfiles/files/susejukusesovog.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_off0000c942.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC942 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e159.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE159 10776 bytes
SHA-256: 2ba95e8c2850c5a77145f4c2bc803e729c53a5cac421a9814c57ee68a0ca8bd4
font_02_sfnt_off0000f9bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9BC 18440 bytes
SHA-256: 61f56ba56f239d3d45f72f262d79e256a63833fabfdec7139c179083469f98b4