Malicious PDF — malware analysis report

Static analysis result for SHA-256 55bc4d4c21d61ee3…

MALICIOUS

PDF

89.9 KB Created: 2021-09-16 11:26:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e9ddcc92895ed213229a764c8012d592 SHA-1: 098ffe100a572fba9d6139175357e9f41175b58d SHA-256: 55bc4d4c21d61ee3c94726ba952aa29fe146cebece95cac73f00caa7bee6b892
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for exploiting PDF vulnerabilities or redirecting users to malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a large number of links to potentially disposable domains, suggesting a phishing or spam campaign. ClamAV detection further confirms its malicious nature, classifying it as Pdf.Phishing.Trojan. The embedded JavaScript likely facilitates the redirection or exploitation, contributing to the overall malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.asoriofrio.org/ckfinder/userfiles/files/nakaz.pdf In PDF document text
    • https://tabularasa.lv/sites/tabularasa/uploads/documents/files/ropazufijesasiganedog.pdfIn PDF document text
    • http://appli-veolia.net/ckfinder/userfiles/files/nodisukomeb.pdfIn PDF document text
    • https://iqrainternationalschool.org/_assets/files/6716275747.pdfIn PDF document text
    • https://mastirz.com/userfiles/files/werejomozulixulagoxujerep.pdfIn PDF document text
    • http://yujinpharma.com/upload/files/nawokukebone.pdfIn PDF document text
    • http://arebiatours.com/uploads/files/59569220673.pdfIn PDF document text
    • http://agppi99.pretty-match.com/upload/files/fizidedibusavi.pdfIn PDF document text
    • http://inventory-acepipe.com/images/uploads/files/jibob.pdfIn PDF document text
    • https://cvzona.lt/resources/img/files/28464362123.pdfIn PDF document text
    • http://autoachtercamper.nl/userfiles/file/11811142814.pdfIn PDF document text
    • https://lp-tracking.com/userfiles/file/1851845125.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139315fc0c27---zutuvilarawirubirawopo.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/12915836768.pdfIn PDF document text
    • https://munis-roquesalbes.cat/demo/vilalba/imatges/file/buzexorasu.pdfIn PDF document text
    • https://cafeau1ait.xyz/js/ckfinder/userfiles/files/53727783371.pdfIn PDF document text
    • http://futimisdev.com/userfiles/file/ziluvepirimozezemumekuwa.pdfIn PDF document text
    • https://www.fibertech1.com/my_content/js/ckfinder/userfiles/files/sevedemuwarisaxedowone.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/16136f27aed18c---80306943785.pdfIn PDF document text
    • http://assytekservizi.com/userfiles/files/bozutalenasa.pdfIn PDF document text
    • http://esrafisek.com/images_upload/files/66710567591.pdfIn PDF document text
    • http://newshop.jp/archive/file/xesobize.pdfIn PDF document text
    • http://elektromig.pl/userfiles/file/robiteviturasawet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=save+call+logs+androidPDF 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://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_off0000fbb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBB6 10588 bytes
SHA-256: 73bd0a36e3f234409ffb01fa624ab7d124ce7e0b578943c5c26715e1225b0c17
font_01_sfnt_off000113bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x113BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012bcf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BCF 17856 bytes
SHA-256: f22895af808bb33a5b999e218cf781fb1f11feaa033f9e2e6942aca2be3fdbe7