Malicious PDF — malware analysis report

Static analysis result for SHA-256 863ba41114f13b8c…

MALICIOUS

PDF

81.5 KB Created: 2021-09-20 14:28:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: d3f2efa0144cb94cd315146b6ad67c1b SHA-1: 25c6123b2502bf15082a4e83ef497417f19c96b7 SHA-256: 863ba41114f13b8cc0d3bd62ac12f1dd60bd45e076d4a04e7f687b4d051b2135
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and multiple external URLs, suggesting it is designed to lure users into downloading and executing further malicious content. The 'SE_CLICKFIX' heuristic indicates the document instructs users to press Win+R or paste a command, a common tactic to bypass security measures and execute arbitrary code, likely to download a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • ClickFix social engineering attack high SE_CLICKFIX
    Document instructs the user to press Win+R or paste a command into a terminal — consistent with ClickFix attacks that bypass macro restrictions by tricking users into running malicious commands directly
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nomylo.ru/uplcv?utm_term=install+ubuntu+dual+boot+windows+7 PDF link annotation
    • https://inoxquochoang.com/app/webroot/files/images/pages/files/jutadejisened.pdfIn PDF document text
    • http://zapatosperezcabrera.com/ckfinder/userfiles/files/giges.pdfIn PDF document text
    • http://saddabro.com/userfiles/file/sutomatag.pdfIn PDF document text
    • http://dailygameresult.com/editor/UserFiles2/files/88221882816.pdfIn PDF document text
    • http://hflchw.com/upload/file/lotiporumobizexefofugo.pdfIn PDF document text
    • https://wic-net.com/userfiles/file/38044640788.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/39273012893.pdfIn PDF document text
    • https://htapigroup3.com/contents/files/43384918710.pdfIn PDF document text
    • http://streetnn.ru/data/upload/ck/files/bomifojibujunabaxika.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/60507094596.pdfIn PDF document text
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614584b161890---wuvibibavibexuji.pdfIn PDF document text
    • https://marwaservicecenter.com/nbloom/fckuploads/file/rerube.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/161377bfa4eef1---68532411095.pdfIn PDF document text
    • https://stpatswatertown.org/ckfinder/userfiles/files/xowipolegikinuxabetolazut.pdfIn PDF document text
    • http://tattooindex.nl/images/uploads/14706308531.pdfIn PDF document text
    • http://linuxnewyork.com/draft/media/jaxorovizidibugedewetosuz.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/90517980421.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/lojiwaf.pdfIn PDF document text
    • http://bptramptour.pl/files/file/kilirenipefogamiz.pdfIn PDF document text
    • http://lngpetro.com/userfiles/file/kivudinokafuwatovavar.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/49646872785.pdfIn PDF document text
    • http://rosritual.su/app/webroot/js/ckfinder/userfiles/files/najozoritugevixukol.pdfIn PDF document text
    • https://basalyemek.com/ckfinder/userfiles/files/kuwemazatunozavamuva.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/61787998283.pdfIn PDF document text
    • http://xn--pr3b03lcdvwu9dpynqkc.com/DATA/file/20210901165901.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_off0000da40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA40 10336 bytes
SHA-256: b0d4bcd23e873a3ee234c4664396fb7bf1d674db75559deb9dee509990305f1b
font_01_sfnt_off0000f1ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BA 18288 bytes
SHA-256: a94f3db894c3925629eaa0fd4e6f463c3019d175459300bfdd388aa503ee1e69
font_02_sfnt_off00012059.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12059 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1