Malicious PDF — malware analysis report

Static analysis result for SHA-256 88ef2aa5949f0a91…

MALICIOUS

PDF

84.5 KB Created: 2021-09-24 09:22:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b0d76b7e537fa6d45a77078f060d7caf SHA-1: 93b57ecbb9543fae21d3e09f1a27dff2c5157d26 SHA-256: 88ef2aa5949f0a91ce099fc6b4fd73fc296ba7fb0796f93412c1ae66f978902c
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9898

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://jeneifogaszat.hu/cikkdata/files/6073134171.pdf In PDF document text
    • https://marathonlaval.com/userfiles/files/85302761299.pdfIn PDF document text
    • http://phucuongplus.com/upload/files/16571460196.pdfIn PDF document text
    • http://www.abcklima.hu/data/editorfile/51010840062.pdfIn PDF document text
    • https://instalacje-elektryczne.net/ckfinder/userfiles/files/maparen.pdfIn PDF document text
    • https://unitedfightalliance.jordanadams.com/ckfinder/userfiles/files/36896803165.pdfIn PDF document text
    • http://bulmarconsult.com/files/bedapezane.pdfIn PDF document text
    • https://ikima.fr/uploads/file/fififovi.pdfIn PDF document text
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b5aceab8bf---kuberezazoju.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/0c72ee9667930a24f22191f085be3333/vetazoxawibabobufum.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/71690421211.pdfIn PDF document text
    • https://trompis-tondschungel.de/userfiles/file/vujinare.pdfIn PDF document text
    • http://studiodrago.eu/userfiles/files/35213296875.pdfIn PDF document text
    • http://ensky-chemical.com/upload/files/wilitulediw.pdfIn PDF document text
    • http://phuvuongcorp.com/luutru/files/71220323734.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/koxogadesefef.pdfIn PDF document text
    • https://cyc-catering.pe/disac/userfiles/file/binapatuganeri.pdfIn PDF document text
    • http://msdoubrava.cz/foto/images/file/69326820427.pdfIn PDF document text
    • http://balade-pierry.fr/userfiles/file/76726022787.pdfIn PDF document text
    • https://omegaplus.bg/uploads/pages/files/watoduvow.pdfIn PDF document text
    • https://gulceoyunlar.com/calisma2/files/uploads/6329231163.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1614599152b2be---38501927155.pdfIn PDF document text
    • http://okudshava.ru/userfiles/file/bisilirugefovuw.pdfIn PDF document text
    • http://pure-chiral.com/upload/files/jomowasokuvob.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=fluid+mechanics+khurmi+pdfPDF link annotation
    • 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://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_off0000eb4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB4D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010364.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10364 10836 bytes
SHA-256: 35bde81d6fa1097edf54fa543742517e4ad9b2ecfda826f236161129fd0450d1
font_02_sfnt_off00011c11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C11 17868 bytes
SHA-256: a6a85720c2a8abf504547e84b67f618c0e1b881b95713bf4fb22b58a5256b222