Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b7d53694bb2b177…

MALICIOUS

PDF

71.4 KB Created: 2021-09-13 14:02:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 32c17aa2e740756829f96fba7cc711d1 SHA-1: 52844c3503d5239448a92334620fba7d5347a123 SHA-256: 7b7d53694bb2b177c6112cc92135333874e24ac4ab18cddb13b8d2cf501ad2e5
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to disposable domains, and is flagged as a link farm. ClamAV and ML classifiers identify it as malicious, likely a phishing or malware distribution lure. Although no scripts were explicitly extracted, the nature of the embedded URLs and the heuristic firings suggest an attempt to redirect users to malicious content, potentially leveraging PDF vulnerabilities or social engineering.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://3asoft.vn/img/files/kumol.pdf In PDF document text
    • https://minjar.mebel18.com/uploads/files/92596348667.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/53553930080.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/ruzusotukubomejuso.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/10214799334.pdfIn PDF document text
    • http://thicongdiennuocmiennam.com/uploads/files/38877504672.pdfIn PDF document text
    • http://meruzhankhachatryan.com/app/webroot/files/file/zeladasokogozuwanebewuwu.pdfIn PDF document text
    • https://abzesolar.com/uploads/files/33699394306.pdfIn PDF document text
    • https://onsale.social-push.cc/data/fckeditor/files/52327074510.pdfIn PDF document text
    • http://restavratorstvo.com/ckfinder/userfiles/files/kuxisidedejizaj.pdfIn PDF document text
    • http://blueview.nl/app/webroot/files/userfiles/files/pilizomepebiwe.pdfIn PDF document text
    • http://aliguoriarchitetto.eu/userfiles/files/73768696327.pdfIn PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/b7f94fa2beea9eadd1347c76b0c77410/kokefoga.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/161375f651b161---36301463335.pdfIn PDF document text
    • http://around-sicily.net/userfiles/file/gulidinavodabamikejavede.pdfIn PDF document text
    • http://trivio.it/userfiles/files/41534070978.pdfIn PDF document text
    • http://basyapiemlak.com/yukleme_klasoru/userfiles/file/30477632212.pdfIn PDF document text
    • http://pentas.eu/userfiles/file/27040582416.pdfIn PDF document text
    • https://we-plus.tw/ckfinder/userfiles/files/dorixavi.pdfIn PDF document text
    • http://hykylalumni.org/userfiles/fevadenojamejafobo.pdfIn PDF document text
    • http://gestioniarmatoriali.it/57860192757.pdfIn PDF document text
    • http://canadapremiumlubes.com/survey/userfiles/files/5792744345.pdfIn PDF document text
    • https://dolphinsolutions.net/ckfinder/userfiles/files/xikif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=iphone+7+mobile+data+not+workingPDF link annotation
    • 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_off0000b5a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cdb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCDB8 10992 bytes
SHA-256: 8a7e604869038c945b4369ba2ee662fa833ca666ea944d60630bcbbafaa8686e
font_02_sfnt_off0000e6a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6A5 16292 bytes
SHA-256: cfe608d241725d5fab38672b30f21fc45f50c01e32c715c6a7ba2243346daec0