Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4438ffa12f03e0a…

MALICIOUS

PDF

74.8 KB Created: 2021-09-17 01:03:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 2f431e46466f7e29f995403a41dc6c8e SHA-1: 7b1a989b2ba8aee0b13cfa133570bef913ed2d38 SHA-256: b4438ffa12f03e0a337e861ae6202155e43ed3e7be273f69231b7e216b863a8a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs that form a link farm, with several pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content. The presence of external URI heuristics and link farm indicators strongly suggests a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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=app+emoji+iphone+for+android PDF link annotation
    • https://comodee.com/wp-content/plugins/formcraft/file-upload/server/content/files/161357c2641963---xinuxavowigubipafewov.pdfIn PDF document text
    • http://werkkledingverkoop.nl/images/docman/files/jotisu.pdfIn PDF document text
    • https://mttrasportisrl.it/dati/upload/file/vujodiginabebibufakaki.pdfIn PDF document text
    • https://theipbuzz.com/images/file/20918077675.pdfIn PDF document text
    • https://hobbes-group.com/upload/files/tetemalamekosogug.pdfIn PDF document text
    • http://www.gieskestukadoors.nl/ckfinder/files/files/bajemawewimaroladekajiw.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16140944825767---20956959753.pdfIn PDF document text
    • https://samsungdvmklima.com/upload/ckfinder/files/14532524695.pdfIn PDF document text
    • http://mamam.by/upload/File/file/momilefepitasisotoguvuwub.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/bezetasofuriko.pdfIn PDF document text
    • https://legouic-peinture.fr/userfiles/file/46622499871.pdfIn PDF document text
    • http://peoplefoster.com/pliki/solitad.pdfIn PDF document text
    • http://rpsbchamber.org/editorData/file/woxufulufizotosamamufu.pdfIn PDF document text
    • https://vinaarc.com/app/webroot/files/ckfinder/userfiles/files/97973024462.pdfIn PDF document text
    • http://scard.vn/app/webroot/uploads/files/93241697222.pdfIn PDF document text
    • http://dj-venci.com/uploads/pages/files/paxuvepiverabowiduz.pdfIn PDF document text
    • https://bluetact.com/locktactyuma/userfiles/file/ludarodibozokodirumaxokuk.pdfIn PDF document text
    • http://hotelclinton.it/userfiles/files/85664152597.pdfIn PDF document text
    • http://eggtesting.com/admin/uploads/file/kotazajigitinefovanujur.pdfIn PDF document text
    • http://www.bash.cl/media/file/2162888986.pdfIn PDF document text
    • http://inbond-cn.com/userfiles/file/59712071636.pdfIn PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/72021751122.pdfIn PDF document text
    • https://loppisidjupdalen.se/images/uploaded/file/25925834501.pdfIn PDF document text
    • http://artio.pl/files/files/kapewewozojiwowatetilo.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.info/upload/files/88726542778.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ab331aeb6---35225115522.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_off0000c25e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC25E 10560 bytes
SHA-256: a3c8271d9430ddc249fe8718c28a7a6cd88bf51599d7f946752205330a4b9d9f
font_01_sfnt_off0000da1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f230.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF230 16772 bytes
SHA-256: be99685c4850b19730acc56fe785b2346e2b2f09b0c8fcdbc28722086bab02b5