Malicious PDF — malware analysis report

Static analysis result for SHA-256 213473c4db97be7b…

MALICIOUS

PDF

87.0 KB Created: 2021-09-11 06:31:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 67828ccbcc9dd20a62a632c578757021 SHA-1: 894d82d2a39cdccd15398d26218e0115756b076e SHA-256: 213473c4db97be7b1529d865fbfe922fa3f440adbc079c6f96269cb98ce324c2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS uploads. The presence of 'utm_term' parameters suggests a phishing or spam campaign aimed at driving traffic to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://allytemp.ru/uplcv?utm_term=asus+transformer+book+trio+android+update PDF link annotation
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/a28def6687faf72c70ddec036dc3cd75/xobabalikokosatan.pdfIn PDF document text
    • https://www.loisirs-auto-occasion.fr/ckfinder/userfiles/files/pifori.pdfIn PDF document text
    • http://aminotp.com/upload/files/kesetegijofigudegur.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/reletifazajikefebujowu.pdfIn PDF document text
    • https://concurs-euclid.ro/upload/fck/99263108724.pdfIn PDF document text
    • http://tainanrup.longi.tw/uploadfiles/files/20210903_105901_3136.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea83c6adb7---51402748785.pdfIn PDF document text
    • http://maihome.hu/admin1/file/34624632281.pdfIn PDF document text
    • http://hamdannepal.com/userfiles/file/67998339007.pdfIn PDF document text
    • http://cleangroupbd.com/ck/upload/files/fobukupigijot.pdfIn PDF document text
    • https://sanghvicranes.com/staging/media/larenatinedute.pdfIn PDF document text
    • http://lenaoyunlar.net/calisma2/files/uploads/kixeniger.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/duziw.pdfIn PDF document text
    • http://szwygs.com/upload/40009048349.pdfIn PDF document text
    • http://rhondachem.com/d/files/51703994331.pdfIn PDF document text
    • https://gservicepz.com/wp-content/plugins/super-forms/uploads/php/files/a47300a6f9b858d3728ed9c721f0e7a1/munatetevekesekabis.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16130a16d79140---12419528380.pdfIn PDF document text
    • https://egokituz.eus/files/galeria/files/nufedediwilaninepinuva.pdfIn PDF document text
    • http://ideviceplus.nl/app/webroot/files/userfiles/files/12576825338.pdfIn PDF document text
    • http://medtravel.pro/images/hand_uploaded/files/4515939496.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135455d70367---39157805000.pdfIn PDF document text
    • https://luatsubienhoa.com/upload/ck/files/16513849649.pdfIn PDF document text
    • http://instalace-charvat.cz/userfiles/file/rakuserimosekoxilo.pdfIn PDF document text
    • https://srsatta.com/ckfinder/userfiles/files/24522668730.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_off0000e9a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9A0 19764 bytes
SHA-256: 787537584b61cc49cc0abba1e96f9a2ea63f3c2c314a0c9fb747ba76e290fddd
font_01_sfnt_off00011d6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D6A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013581.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13581 10928 bytes
SHA-256: 30cf2d52583014d3a67aeb60f14d261076dc741c6c279b65473609b4bd3ae32f