Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcdd62273bcafab8…

MALICIOUS

PDF

78.5 KB Created: 2021-09-11 16:18:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 12b2635daa327df04abfd0ce9629237b SHA-1: f6a4e8d0868157227776cb5bb74af5992022d221 SHA-256: dcdd62273bcafab8e69a2a9ddcc348da8bb35bc37c4e115bb950d1375c750437
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF containing multiple links to external websites, several of which are hosted on compromised or disposable domains. The heuristic PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM indicate a pattern of distributing malicious content through these links. ClamAV detection and ML classification further support its malicious nature, suggesting it's used for phishing or to deliver further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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=how+to+send+a+video+from+android+to+iphone PDF link annotation
    • http://kibbkw.com/uploads/files/zediwonifuforu.pdfIn PDF document text
    • http://aqua4you.hu/userfiles/file/texazekusivanapa.pdfIn PDF document text
    • https://digireg.nu/upload/65689185189.pdfIn PDF document text
    • http://sibleyestateplanning.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fafetuvemaronuwa.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/pjms99vnnepqba0umpac6b9785/fiwisekidefop.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/84973ba6fed68813885197d67c6c1672/4634810801.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/98319673318.pdfIn PDF document text
    • http://senseoftourism.dk/userfiles/file/78884833018.pdfIn PDF document text
    • http://iccarrentals.com/files/file/sagabekunufulo.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/87204314217.pdfIn PDF document text
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/65ee8f41b4eef97e78f32512a7eacd78/46476133839.pdfIn PDF document text
    • https://maisonforville.be/documents/file/76772565865.pdfIn PDF document text
    • http://www.atsamuihaus.com/image/upload/File/2113354549.pdfIn PDF document text
    • https://childrencareandliteracysociety.org/userfiles/files/fejinoluwosub.pdfIn PDF document text
    • http://humanlitech.com/files/files/7125408336.pdfIn PDF document text
    • http://nghiencuuykhoa.com/uploads/userfiles/file/tokavowap.pdfIn PDF document text
    • http://kftchem.com/upload/files/tumutumupejemosegekamani.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_off0000ce9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE9D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e6b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B4 10860 bytes
SHA-256: 73f6a4f67292358212640710c818ac47e909d217745dcf203d7ace33a94db136
font_02_sfnt_off0000ff9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9D 17764 bytes
SHA-256: bc950fcc9e5e53652eb01c91aa0f8a3f4106a3ddc7e0717f51a76bc9177c793f