Malicious PDF — malware analysis report

Static analysis result for SHA-256 203fd938cbec1871…

MALICIOUS

PDF

99.4 KB Created: 2021-04-18 00:51:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 7ebdc518af68348c7359f8bd5ac868bc SHA-1: 57fd4ddb6649a8fc1062d0f539c1daf3a2f46982 SHA-256: 203fd938cbec18716b07ca700ce03f4890e1d49a2513c4c895ba7a620907e87b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which are hosted on seemingly legitimate domains but are part of a link farm, a common tactic for phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to a malicious site, likely for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.newburghgroup.com/sites/default/files/webform/resumes/talazeleravu.pdf In PDF document text
    • https://ambrose.edu/sites/default/files/webform/20598750849.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/17654710786.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/19824824677.pdfIn PDF document text
    • https://architecturaldesigninc.com/sites/default/files/masugikiretige.pdfIn PDF document text
    • https://ambrose.edu/sites/default/files/webform/9979090083.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/wibojamivumararevede.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/xexazud.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/31626011693.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/17232120942.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/bedadijone.pdfIn PDF document text
    • https://web.liderpapel.com/sites/default/files/webform/wavunivuzabanovomid.pdfIn PDF document text
    • https://www.woonsocketri.org/system/temporary/webform/bogobovimefegaf.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/41319995155.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=evidence%25E2%2580%2590based+strategies+for+reading+instruction+of+older+students+with+learning+disabilitiesPDF link annotation
    • https://community.princeton.edu/system/files/webform/4167827641.pdfIn PDF document text
    • https://thesanfordschool.asu.edu/sites/default/files/webform/lezedatabamivija.pdfIn PDF document text
    • https://lib.asu.edu/system/files/webform/bejugejotofetuxiw.pdfIn PDF document text
    • https://ec.europa.eu/eip/agriculture/sites/default/files/webform/72323592377.pdfIn PDF document text
    • https://community.princeton.edu/system/files/webform/36479690150.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://scripts.sil.org/OFLIn 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_off00012f23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F23 5532 bytes
SHA-256: b59c7f43e7e6258288239e6ee5a422d52ffb5a09476e1d4240555b72245cc755
font_01_sfnt_off00014206.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14206 10580 bytes
SHA-256: fe2848aa37e9973786941c984815af281daed687cb458c767a8a78348bcb44e3
font_02_sfnt_off0001667d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1667D 16112 bytes
SHA-256: b9a2134a75fa7dcfb137954930e794e7f9d2e52df73b3f035c73dbae7575d794