Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c831623386cacca…

MALICIOUS

PDF

83.5 KB Created: 2021-09-19 00:56:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9411ea2feead621a64cee3c4812400a8 SHA-1: fe8e770a46e9eca9c6f164e2c3ca2ded355e4e21 SHA-256: 1c831623386cacca7371020598d81a3a56028cf5b0b1a98a2a22248eb566463f
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to suspicious domains, and is flagged as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and URL patterns suggest it's designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 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.
  • 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://pixomot.ru/uplcv?utm_term=adview+android+studio PDF link annotation
    • http://alacartedesign.de/userfiles/file/rakupos.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/lenavuwolekodelujat.pdfIn PDF document text
    • http://lakshimi-kaatsu.com/user_data/packages/default/imgfiles/11606052981.pdfIn PDF document text
    • https://taichielite.com/louis/taichi/ckfinder/userfiles/files/rinewesomifutapirogef.pdfIn PDF document text
    • https://primer-spb.ru/files/files/xavogediloravebeniravaz.pdfIn PDF document text
    • http://yljczl.com/uploadfile/20210914084407959.pdfIn PDF document text
    • http://lucidarepavimentimarmogenovaealessandria.it/userfiles/files/zufidekasegik.pdfIn PDF document text
    • http://iraneto.com/basefile/iranetocom/files/niwekuzoj.pdfIn PDF document text
    • http://www.iciparis.ru/ckfinder/userfiles/files/durukanetoxojenewoxem.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/47783069345.pdfIn PDF document text
    • http://asiadomainstore.com/userfiles/file/disuterugudofusel.pdfIn PDF document text
    • http://techniq.ae/admin/uploadfiles/file/kewerutuzonuruvagevul.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613d5b16689de---jupenerobufokisiwobogijen.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135fa7e6bc28---22705214194.pdfIn PDF document text
    • http://bn-biz.com/userData/board/file/woliji.pdfIn PDF document text
    • https://seedomoretravel.com/files/files/4994294814.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109190555205019.pdfIn PDF document text
    • https://haruhonpo.com/upload/haruhonpo/files/24338016478.pdfIn PDF document text
    • http://baldonimarcostudio.eu/userfiles/files/93726128110.pdfIn PDF document text
    • https://petribax.com/userfiles/file/85521821434.pdfIn PDF document text
    • http://wmasgroup.com/userfiles/file/vojebuwokatudajij.pdfIn PDF document text
    • http://nmways.com/uploads/fckupload/file/rozuxopenosapa.pdfIn PDF document text
    • http://hasicimosnov.cz/foto/Image/file/positele.pdfIn PDF document text
    • https://scout-educationguide.com/userfiles/file/sajanifinap.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_off0000e140.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE140 18180 bytes
SHA-256: 09486858c91f9d868facf564c71ca925b8557923636b32ce4f84352b26edbb69
font_01_sfnt_off00011030.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11030 10428 bytes
SHA-256: 14cabb299fa74463e1b96e74cc139105e866c87b948fb140b4f207915fc06417
font_02_sfnt_off00012814.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12814 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1