Malicious PDF — malware analysis report

Static analysis result for SHA-256 163216f1a031d578…

MALICIOUS

PDF

69.2 KB Created: 2021-09-24 15:48:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: b7da9210177b6add6647a085cdc7d0da SHA-1: 1502ee9946402badf617dae7f0378623f7441aae SHA-256: 163216f1a031d578b56b65a235900496e26af15da144f751cc820a92230a6e0e
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

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://pixomot.ru/uplcv?utm_term=dinosaur+game+ipad PDF link annotation
    • https://askisan.com/upload/ckfinder/files/gapezivoz.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/koxasoximeduvur.pdfIn PDF document text
    • https://cradlegold.com/wp-content/plugins/super-forms/uploads/php/files/h1k7q4oh3r2c96n5f0m5dncrd1/27841836937.pdfIn PDF document text
    • http://megalaserasia.com/upload///90310400695.pdfIn PDF document text
    • http://auburn-properties.com/userfiles/files/seniw.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16139fd36bacb3---razaroladobekodoro.pdfIn PDF document text
    • https://holcom-wd.holcom.vn/webroot/img/files/mipimuwoxovom.pdfIn PDF document text
    • http://yuseigachi.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16143ecb510c27---lunaxaro.pdfIn PDF document text
    • http://canoto.us/Images_upload/files/jaximoxigamatifeluzoraf.pdfIn PDF document text
    • http://millionsdiscount.com/mo_images/files/80067098209.pdfIn PDF document text
    • http://taaltoetsvo.nl/userfiles/file/ziwenisodapufixomatotagor.pdfIn PDF document text
    • https://viceda.com/userfiles/file/89179979558.pdfIn PDF document text
    • https://www.koreayokogawa.com/ckfinder/userfiles/files/mapixanikolezokokif.pdfIn PDF document text
    • http://tcihk.com/userfiles/30204617328.pdfIn PDF document text
    • https://bibliotheque-des-arts.com/ckfinder/userfiles/files/moxilu.pdfIn PDF document text
    • https://b7b.reviewz.eu/app/webroot/files/userfiles/files/baketukajoxawopuxikipabox.pdfIn PDF document text
    • http://urgentcarepb.net/userfiles/file/zawijorinumewekazejufep.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/nivekalelavezukagal.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161452e56e79dc---wezexopodopik.pdfIn PDF document text
    • http://119pump.net/d/files/4690600171.pdfIn PDF document text
    • http://zakuskymoser.cz/www/ckfinder/userfiles/files/88563415657.pdfIn PDF document text
    • http://rgn2u.com/userfiles/files/lofebopumukipukoron.pdfIn PDF document text
    • https://currenwatch.myhost360.cn/file/upload/files/09-15-13-37-49-38.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_off0000b129.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB129 10692 bytes
SHA-256: 9c21ca793f684d790e03a320ee885023e0107d8bd4154730487d96d3e80859b7
font_01_sfnt_off0000c964.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC964 14984 bytes
SHA-256: 9eec36e5b8d3f9b17b4c94fcb74526c65f98f98d16feaf989b9a1efcaf61eaf2
font_02_sfnt_off0000ef34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF34 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1