Malicious PDF — malware analysis report

Static analysis result for SHA-256 44101a26b8d37707…

MALICIOUS

PDF

73.5 KB Created: 2021-08-25 00:51:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 4331cc9d3383bdc4b7d237826a4c14c8 SHA-1: 43869f7e8e5a86c511fa8002d73624f29abf5742 SHA-256: 44101a26b8d377075efe7abe9f4838c874a1906b7cf935afa7332d06bf16ad87
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to a variety of domains, many of which appear to be compromised or disposable. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery through these links. The document structure and URL patterns are consistent with a link farm designed to obscure the ultimate destination and evade basic detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://allytemp.ru/uplcv?utm_term=complete+the+conditional+sentences+with+the+correct+form+of+the+verbs+in+brackets PDF link annotation
    • http://m2mus.pro/clients/b/b1/b1ca46fdb12d68e762e4a8b3318caec0/File/pelawul.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa3c274ed59---32609957492.pdfIn PDF document text
    • https://wfca-czech.cz/temp/userfiles/files/90725994819.pdfIn PDF document text
    • http://juha.be/_files/file/46733369324.pdfIn PDF document text
    • http://runbo.net/upfiles/files/16288339722183.pdfIn PDF document text
    • https://tranduongauto.com/app/webroot/files/images/pages/files/18814188453.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/27129429591.pdfIn PDF document text
    • http://thekitchendesignstudio.org/uploads/files/28886711590.pdfIn PDF document text
    • http://aeskulap24h.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba0d85cc8b---xebibabajezugunezaludi.pdfIn PDF document text
    • https://balajitutorial.com/admin/userfiles/file/94728431267.pdfIn PDF document text
    • http://cassotech.nl/site/data/ws/files/53473579016.pdfIn PDF document text
    • https://uaqbakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d57b224552---gurojunulomex.pdfIn PDF document text
    • http://nhaphangmy.us/upload/files/51859398874.pdfIn PDF document text
    • http://brenna-ski.pl/userfiles/file/400254238.pdfIn PDF document text
    • https://t2sc.me/userfiles/9653650333.pdfIn PDF document text
    • https://purpleleafestatebuyers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076abd31e56f---luxorogop.pdfIn PDF document text
    • https://www.enterpriselighting.com/wp-content/plugins/super-forms/uploads/php/files/3fbd4a053fa8180b532d739f5c8ac34a/gutaneluposu.pdfIn PDF document text
    • http://xn--54-dlcdkamdj4btild5b.xn--p1ai/ckfinder/userfiles/files/tizen.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/10524230186.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/03ies0qfld8r1comgruchv1e7k/zasepabewoxironot.pdfIn PDF document text
    • http://cafegreenwichvillage.com/uploads/files/94097971199.pdfIn PDF document text
    • http://izdo.org/img/userfiles/files/24901143759.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://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_off0000be6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBE6D 15608 bytes
SHA-256: c5dd1d3323bc737fa5a0f14783c18bdc68c9f69dcff28db2fb4762d349fa46f9
font_01_sfnt_off0000e638.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE638 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fe4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE4F 11300 bytes
SHA-256: 42dffc9a6f189b081144465a97fd739bdda3557738a2f4826a55e9751f27161e