Malicious PDF — malware analysis report

Static analysis result for SHA-256 72138466cfe491d8…

MALICIOUS

PDF

75.0 KB Created: 2021-09-29 15:03:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 5eb2c1836a1b6a6264115213d6cedaed SHA-1: bf2eb94ff32c1d1da2c4de040f8e3f295f6be1e2 SHA-256: 72138466cfe491d8abb41609ad10e61314ba5ef99777ea6e877b980a47095aec
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous external URIs, including one that appears to be a redirector with UTM parameters, suggesting a phishing or malware distribution lure. The PDF structure and embedded links indicate it's designed to direct users to potentially harmful external websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://drafthe.ru/uplcv?utm_term=best+unfollow+app+for+instagram+2021+free PDF link annotation
    • http://koreanhotpot.com/uploads/files/pinixezufikurarugib.pdfIn PDF document text
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/59243942474.pdfIn PDF document text
    • https://sakesushimn.com/userfiles/files/90089387344.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/27544245902.pdfIn PDF document text
    • http://imosa.asia/uploads/files/202109261036585640.pdfIn PDF document text
    • https://conrays.ru/f/data/wuzunuxeviwajemaduw.pdfIn PDF document text
    • https://hearing-outlet.com/uploads/files/202109281828373988.pdfIn PDF document text
    • https://santa.sg/images/users/00000000/files/rusidiwerod.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/raguluboxixilozivuzep.pdfIn PDF document text
    • https://mldom.xyz/web/img/podborky/files/zavotinobubu.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613af66665101---sivejowamofaneronupozuxet.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/zimufanoli.pdfIn PDF document text
    • http://systempro.kr/userData/board/file/35703255312.pdfIn PDF document text
    • http://kirilmazbardak.com/userfiles/file/xutititemulegazugovek.pdfIn PDF document text
    • http://www.mostex.sk/files/articles/file/jopagomoxajasejuvulato.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/80069333510.pdfIn PDF document text
    • https://serwisnawigacji.pl/userfiles/file/lurexoxogigozedam.pdfIn PDF document text
    • https://reha.bg/content/upload/file/61107182866.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/ecb6bc71b6193a67f813594710387cfd/29480316849.pdfIn PDF document text
    • https://andana.us/files/files/fibosefowogajuromapiveto.pdfIn PDF document text
    • http://korsorlampang.net/user_img/files/30553114855.pdfIn PDF document text
    • http://agisma.ru/files/pages/files/28101061951.pdfIn PDF document text
    • https://megacook.pt/site/upload/file/86738357007.pdfIn PDF document text
    • https://anitacalderon.com/ckfinder/userfiles/files/56271321075.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/65669878283.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_off0000ba98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA98 19188 bytes
SHA-256: b93808fb0e59f2b97b8d3976035e1513867bbc94f1d7a63f6f65508eaabd49bc
font_01_sfnt_off0000eb23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB23 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001033a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1033A 11232 bytes
SHA-256: f62946c9c8d839f4d75376115fd28b563498493afb9ea399beca682794c6d381