Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb5d7d8b1a8f380f…

MALICIOUS

PDF

77.2 KB Created: 2021-09-17 00:28:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 10cab3eea07d0b972e910d35b0d25431 SHA-1: 32ce09449b1615ef99689984897727f3f2478cfc SHA-256: bb5d7d8b1a8f380ff498d7a6b8274fc38a8be1d8a86375c410f9a5802882f597
196 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ClamAV as a phishing trojan. Heuristics indicate it's a link farm and uses social engineering ('ClickFix') to prompt the user to run a command, likely to download a secondary payload. The embedded URLs point to potentially compromised domains, suggesting a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • 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
  • 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://oniceh.ru/uplcv?utm_term=how+do+you+take+off+safe+mode+on+an+android
    • http://zerosquareonline.com/file/renurom.pdf
    • http://drukarnia-warszawa.pl/pliki/file/7678167973.pdf
    • https://wscnaturalhealings.com/wp-content/plugins/super-forms/uploads/php/files/62111a1a702f46ae591d0a12c2a9859a/43484378441.pdf
    • http://bimbrlata.cz/UserFiles/File/61456178024.pdf
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143b1e9ea6bf---dutejazege.pdf
    • https://www.db-ynox.fr/ckfinder/userfiles/files/53066876520.pdf
    • http://cheapneasytrafficschool.com/CheapNEasyTrafficSchool/pa/trainstation/uploads/image/file/39040867339.pdf
    • http://hongdacable.com/d/files/vewirilinevepuxed.pdf
    • https://hotelite.in/userfiles/file/fivoxufozaja.pdf
    • https://ijp2.com/contents/files/repapuwapowuneve.pdf
    • http://hk-bbc.com/upload/file/66859993508.pdf
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/wapebatevetipibirefirew.pdf
    • https://artedeeducar.com.br/ckfinder/userfiles/files/wemuwijikijowabari.pdf
    • https://independentmusicleague.com/wp-content/plugins/super-forms/uploads/php/files/5116bf8516069309abb8ff2735d9d1d6/47937504542.pdf
    • https://roarmysecurity.ro/mm/file/vopotegiteg.pdf
    • http://shriadinathbank.com/uploads/tumefa.pdf
    • http://studioscoponi.eu/userfiles/files/gunuranuvomita.pdf
    • http://nacyc.jp/Upload/file/87155630955.pdf
    • http://starinviter.com/ckimagefiles/takuzarebilemukasugun.pdf
    • https://alansglobalservices.com/ckfinder/userfiles/files/wunutiwanexededinina.pdf
    • http://haitrungkim.vn/uploads/userfiles/file/gifezonikalupopulonemaru.pdf
    • http://hai-bi.com/uploads/files/202109130454066692.pdf
    • http://sprinter-lab.ru/content/File/supotuwezajasugifuxerebid.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c7f4.bin
669070386a2bae736306b77e9403faa69be2c1ef6d951fac12c21f9537753c1e
pdf-font-stream PDF embedded font (sfnt) at offset 0xC7F4 17556 bytes
font_01_sfnt_off0000f550.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF550 16792 bytes
font_02_sfnt_off00010d67.bin
7e36a7857756a474dd868c30d5f7a36e0183cf25f3c8de65335a5cb442729b13
pdf-font-stream PDF embedded font (sfnt) at offset 0x10D67 10852 bytes