Malicious PDF — malware analysis report

Static analysis result for SHA-256 916d11c8c99a45d8…

MALICIOUS

PDF

74.1 KB Created: 2021-10-05 06:57:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 19a61845383afdbad0f05328810d659f SHA-1: 69ea3c9ffd69cb412b1db3129573523f3b0c0941 SHA-256: 916d11c8c99a45d86ca964e00a83873d9d450c3e6ccdef0b2af978a591a0d491
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ML classifiers and ClamAV as malicious, specifically indicating a phishing or trojan threat. The document contains numerous embedded URLs, many of which point to compromised WordPress upload storage or disposable hosting, suggesting an attempt to distribute malicious content or phish for credentials. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, indicating a link farm strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://krisoc.ru/uplcv?utm_term=how+does+corn+pop+into+popcorn PDF link annotation
    • https://tomclarkvoiceovers.com/userfiles/files/bozoni.pdfIn PDF document text
    • http://cissi.it/userfiles/files/53029921630.pdfIn PDF document text
    • https://www.alugutader.fr/ckfinder/userfiles/files/veruletizavavoxuxodi.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/43344995782.pdfIn PDF document text
    • http://xn--m1age8bh.xn--p1ai/files/file/mapabawinokeluxelinufadeb.pdfIn PDF document text
    • https://ourlady-schools2.com/userfiles/files/51529129512.pdfIn PDF document text
    • http://ericshartman.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/5863243679.pdfIn PDF document text
    • https://ajansnigde.com/resimler/files/wiwisegejirikanobitapiwo.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/kowogetimoxexepikexis.pdfIn PDF document text
    • http://hoteldarim.ir/basefile/hoteldarimir/files/72935292870.pdfIn PDF document text
    • http://kkc1.org/htdocs/cljr/data/files/depififijafes.pdfIn PDF document text
    • http://dongphat.net/upload/files/3635074285.pdfIn PDF document text
    • https://relans-nn.ru/images/docs/file/17538480472.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210927102120.pdfIn PDF document text
    • http://ciarajewellery.com/editor_upload/file/64463817908.pdfIn PDF document text
    • http://vatlieulamnha.com/media/ftp/file/21723515500.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/cs5lrcgp2a786ru17ahoo8gnm8/6582645256.pdfIn PDF document text
    • http://genarchi.com/data/temp/file/99722643243.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16155c22dc6888---6975069402.pdfIn PDF document text
    • http://sieuthicayxanh.vn/webroot/img/files/jexufuzaxezovopad.pdfIn PDF document text
    • http://kommunikator.nu/demo/userfiles/file///felaletidasuwexal.pdfIn PDF document text
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/kots1ja0btcm7dr2g4f8u4qj6c/ruloxonatexajidanojegapa.pdfIn PDF document text
    • http://schroniskoorzechowce.pl/ckfinder/userfiles/files/nuxovexasikomi.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_off0000bda4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBDA4 17824 bytes
SHA-256: 93c0a87a5f4514adb8cb8e72effb00f632a3f2aa996179dc6a4b5190da39b892
font_01_sfnt_off0000eb28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB28 10376 bytes
SHA-256: 92095de472de331122520b816b54ca800371891d3ecfa212158499ecfd577ccb
font_02_sfnt_off000102b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102B8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1