Malicious PDF — malware analysis report

Static analysis result for SHA-256 2f451575ca9757d0…

MALICIOUS

PDF

82.9 KB Created: 2021-09-15 10:50:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9b8ccd923f6100e14425f68353417981 SHA-1: 5f1d77364fd57bea8daf3efb6dd820d628766b0c SHA-256: 2f451575ca9757d0580ee1607c5bde3f9a794d70da03fce4a6660794b278ed93
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF containing numerous embedded URLs that form a link farm, with several pointing to compromised WordPress upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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
  • 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=android+development+linux+or+windows PDF link annotation
    • https://emenu.hu/editor_up/11473765402.pdfIn PDF document text
    • https://zebcom.in/userfiles/file/gegefedirenilem.pdfIn PDF document text
    • https://responsible-tourism-alliance.com/content_file/files/witifenopadobebu.pdfIn PDF document text
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/pipitifitulinepekojof.pdfIn PDF document text
    • https://lienlacanien.com/img_pages/file/vojes.pdfIn PDF document text
    • http://lawyergz.net/uploadfile/files/zoxinefamuxezalamipowaget.pdfIn PDF document text
    • https://atrax.eu/userfiles/file/65992475489.pdfIn PDF document text
    • https://chiataiec.com/userfiles/Proj_Name/files/8192792708.pdfIn PDF document text
    • https://qkon.ca/images/file/70067465744.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/16d10f88b2d89164edb013374c43d2ca/89693815464.pdfIn PDF document text
    • https://mosallaesf.ir/uploads/ck/files/43571396584.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/c4fe3b8525e91deb605d7ae61b05e244/84589126125.pdfIn PDF document text
    • https://leanuslab.com/UserFiles/file/15913105344.pdfIn PDF document text
    • http://ablerexthailand.com/userfiles/files/73587374862.pdfIn PDF document text
    • https://ermolino.mebel18.com/uploads/files/lofoxonawegaro.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613553ec0dcc7---23068979791.pdfIn PDF document text
    • http://smartvoicecom.com/userfiles/gamufudawakarolizixotite.pdfIn PDF document text
    • https://mimpishio2.net/contents/files/terabanogirefokeli.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/35459884695.pdfIn PDF document text
    • https://almondzwealth.com/administrator/imagetemp/file/julevojisun.pdfIn PDF document text
    • http://www.supair-lux.hu/ckfinder/userfiles/files/83572395785.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_off0000dc31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC31 18592 bytes
SHA-256: a9237cb5e9049f196ab10e354b9fbe9c86989f3662af511b28823508ff97761c
font_01_sfnt_off00010d2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D2B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012542.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12542 10728 bytes
SHA-256: 5cb5c492f2ca49f39a1f9e48df72e45cd8987186e3ae67ca798f5701955453fb