Malicious PDF — malware analysis report

Static analysis result for SHA-256 b04d6423040b9ccc…

MALICIOUS

PDF

80.1 KB Created: 2021-09-18 04:24:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 59bc8d86f2342a0d82592b87fae59437 SHA-1: 5c17d52568c9843b3e48786d8f441deb4cf2c1b4 SHA-256: b04d6423040b9cccb043d0d5c3fd02d18306ef602e3017b668883c83a8ce344f
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to PDF files hosted on various domains, some of which appear to be compromised CMS uploads. This suggests a phishing or malware distribution scheme where users are lured to click on links that lead to further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://xn--o79av69abka850ab6c.com/upload/file/202109061551258425.pdf In PDF document text
    • https://triatlonshop.cz/userfiles/file/zufewomibajowed.pdfIn PDF document text
    • http://www.jimenez-casquet.com/wp-content/plugins/formcraft/file-upload/server/content/files/161390fc1061b4---gavaletoloxadadeg.pdfIn PDF document text
    • http://fujiya-burbank.com/uploads/files/xoguvezibupifajefuzokud.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/92739723999.pdfIn PDF document text
    • https://samsungklimamodelleri.com/upload/ckfinder/files/44598055999.pdfIn PDF document text
    • http://galettedesrois.hu/userfiles/file/60682839786.pdfIn PDF document text
    • http://baozhaopharma.com/upload/files/wofanawuxapenimuwo.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/durufawapuromid.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/28808828071.pdfIn PDF document text
    • http://boras-sjuharad.boj.se/uploads/userfiles/files/31940629718.pdfIn PDF document text
    • https://eminencesolutions.in/resources/userfiles/file/bamonutaxetokeri.pdfIn PDF document text
    • http://world-spa-resorts.com/dok/gesuwojuxuwo.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/rovipexijunafapaxomuzuwus.pdfIn PDF document text
    • http://informerfitness.com/wp-content/plugins/super-forms/uploads/php/files/cf6617c8ddfd3693597de4b141dfc054/10240119307.pdfIn PDF document text
    • https://cncunse.com/d/files/8024520175.pdfIn PDF document text
    • http://donateagift.eu/userfiles/file/zikewerogop.pdfIn PDF document text
    • https://maviet.vn/upload/files/kukiboxudikeleba.pdfIn PDF document text
    • http://villacappuccina.com/userfiles/files/11918147858.pdfIn PDF document text
    • https://clickbox.ro/images/file/86744080114.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137b45f0c34a---61989718550.pdfIn PDF document text
    • http://espressobuilders.com/app/webroot/files/userfiles/files/wugajaxerewinezumi.pdfIn PDF document text
    • http://vizesblokk.hu/files/file/41925526448.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=offline+android+puzzle+gamesPDF 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_off0000d6be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6BE 16388 bytes
SHA-256: c7431cd18e8899602de55b3fa70ed2afe9c085bb95f9f4cca185fd97815089eb
font_01_sfnt_off00010152.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10152 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011969.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11969 10928 bytes
SHA-256: 96e96304fca9c3aa5bb851afb60bf8f7186e2734133e52f6a901aaaa73f5bfc0