Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6d5e93e1ac3355d…

MALICIOUS

PDF

69.8 KB Created: 2021-09-26 08:19:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a6e64dea9594f79a6c337d9bb905c804 SHA-1: 4a5e62ce2f6acf8f5604fe2194042608318da218 SHA-256: f6d5e93e1ac3355df53a08a57f889285d8fb488eb2a018093aa3904ce52268ab
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicate a high probability of maliciousness. The document functions as a link farm, containing numerous URLs pointing to compromised CMS uploads and disposable hosting, suggesting an attempt to lure users to malicious sites. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://krisoc.ru/uplcv?utm_term=what+is+composite+number+and+prime+number PDF link annotation
    • https://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/70997e7b5fdc4c1a23861fe8f57c7d09/tazuzo.pdfIn PDF document text
    • http://halanmilk.com/upload/files/62250418515.pdfIn PDF document text
    • http://dpsnowodworze.pl/userfiles/file/61741403938.pdfIn PDF document text
    • http://lepal.sk/ckfinder/userfiles/files/vazotufudepapi.pdfIn PDF document text
    • http://posicert.com/upload_fck/file/2021-9-5/20210905143312693353.pdfIn PDF document text
    • https://zoorichi.com/temp/fckeditor/file/35977613325.pdfIn PDF document text
    • https://greenlakecruises.com/ckfinder/userfiles/files/606097397.pdfIn PDF document text
    • http://as-eng.biz/userfiles/file/91017582779.pdfIn PDF document text
    • http://zxpgw.com/userfiles/file/dinawogujupezowup.pdfIn PDF document text
    • http://ttmplus.com/userfiles/files/penaju.pdfIn PDF document text
    • https://rtvpuls.com/ckfinder/userfiles/files/15093100616.pdfIn PDF document text
    • http://lerucherdesanges.fr/userfiles/file/nawaviworanikafetegokutes.pdfIn PDF document text
    • http://ukrfirework.com/images/file/buforalale.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1614f547234156---20617229289.pdfIn PDF document text
    • https://domilot.com/uploader/files/27458350433.pdfIn PDF document text
    • http://www.solarwindependence.com/ckfinder/userfiles/files/7566252535.pdfIn PDF document text
    • http://kavtas.com/images_upload/files/29708076183.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/23890377127.pdfIn PDF document text
    • https://metricgroup.it/uploads/file/debetib.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e7e98e6626---tosigopitifixoduzasu.pdfIn PDF document text
    • http://recrute.fr/files/files/bejopotefojumelol.pdfIn PDF document text
    • http://feynburg-uhren.de/uploads/75574373955.pdfIn PDF document text
    • http://keyflounge.nl/userfiles/file/31629626748.pdfIn PDF document text
    • http://olddieselparts.com/ckfinder/userfiles/files/fativizofu.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_off0000b04b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB04B 10968 bytes
SHA-256: a4ab8909bbd82279f7e555f0c21cd56410c477a52766b903d51f3a21dc0b5382
font_01_sfnt_off0000c963.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC963 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE175 15784 bytes
SHA-256: a67bee9d367c2cfc580290a16d9d59bb8c456a0d1d2e1847d50280cbde5f6a54