Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b9f15f9d512dddd…

MALICIOUS

PDF

95.8 KB Created: 2021-07-01 00:25:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f905171d40a82aaa40062b70e81236e4 SHA-1: 0dc9c0fd5dedee6bce2a1f34e8d890708107dd71 SHA-256: 3b9f15f9d512dddd52138c3ba095b1f8c496872ec2c78a22d4bc24af295b2ff6
156 Risk Score

Malware Insights

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

The sample is identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to external sites, some hosted on compromised CMS uploads and disposable domains. These links likely serve as lures for phishing attacks or to distribute further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9825

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 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://noihoithanhtuan.com/media/ftp/file/sazuji.pdf
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/41442b6a96d767ca6f96ae10574733ec/86186516111.pdf
    • https://diedacorporation.net/freesiafiles/file/63983011252.pdf
    • https://triangle-electronics.com/assets/userfiles/file/fikapeladi.pdf
    • https://coebmsf.com/userfiles/file/litow.pdf
    • http://webinaris.net/ckfinder/userfiles/publics/files/vorugax.pdf
    • https://doctornhospital.com/banglanews24/editorsfiles/files/rizaxazesanox.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/t9dkdt857k5613fdp2bnhgean2/zulolalododuzozagipogipup.pdf
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbcb58cc1a2---vamutibosudegurik.pdf
    • https://www.18fire.com/wp-content/plugins/super-forms/uploads/php/files/e4ef0e23a36c546969de60eb5a05b58c/69903070198.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a76b27942b---vugewive.pdf
    • https://choiceenergynetwork.com/wp-content/plugins/super-forms/uploads/php/files/84632bc179ebf29e3d29fa504862812a/92537170988.pdf
    • https://aawyx.com/sites/default/imageuser/file/51193171969.pdf
    • https://menu2uplus.com/images/file/jesinimabad.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9b0e78694e---18737114811.pdf
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/499de5ca5c1d6ebde0d435065cb4b652/11808778234.pdf
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/4bd6c0ef9e1ecb782fe3c08c513f40f8/vugesojitaxijigatavawuf.pdf
    • http://pcwenhua.com/uploadimg/file/16233170301376122316.pdf
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/16093ca574ce7e---fepanakudad.pdf
    • http://atol-res.pl/uploads/file/pavonin.pdf
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d77c77605---jugiko.pdf
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0e50c551e0---63408668550.pdf
    • https://clubslotalmatriche.com/calcas/file/bejodujufike.pdf
    • http://chokmanee.com/userfiles/file/11471329264.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=courgette+stir+fry
    • 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f139.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF139 16792 bytes
font_01_sfnt_off00010950.bin
3d8ceed832b508299451e77cfcda5cf76bafca790bb5007b3ec4aae8afa4a6bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x10950 10320 bytes
font_02_sfnt_off000120c3.bin
641829afe3c2faf2cb8c5798661b0e0806f29a4283bbc9b1440494756df0add5
pdf-font-stream PDF embedded font (sfnt) at offset 0x120C3 2808 bytes
font_03_sfnt_off00012c65.bin
a4619b43bb496f9e300b53984765e575b8a9d1e1b9d6d96767a403377e6e674c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12C65 17256 bytes
font_04_sfnt_off00015954.bin
45380fb9c3273dbff9b58c05d3c376748b6e74be4581952706bc920728196f14
pdf-font-stream PDF embedded font (sfnt) at offset 0x15954 16628 bytes