SNMP second GET not work on 8.5.1 (wok ok on 8.5.0)

[safelock1]

### Description

Affected Page URL
no

Describe the bug
In php I use snmp get

$session = new SNMP(SNMP::VERSION_2c, '10.55.42.100', $snmp,300000,3);
  $suma=805912320;
  list($nic,$signal) = explode('"',$session->get("1.3.6.1.4.1.3902.1015.1010.1.1.1.29.1.5.$suma"));  **//<-this work ok**
  list($nic,$onoff) = explode(':',$session->get("1.3.6.1.4.1.3902.1015.1010.1.7.4.1.17.$suma"));   **//<-not ok and next not work. no error**
  list($nic,$updown) = explode(':',$session->get("1.3.6.1.4.1.3902.1015.1010.1.1.1.5.1.2.$suma.1"));
  list($nic,$deregister) = explode('"',$session->get("1.3.6.1.4.1.3902.1015.1010.1.7.4.1.16.$suma"));
  list($nic,$register) = explode('"',$session->get("1.3.6.1.4.1.3902.1015.1010.1.7.4.1.12.$suma"));
  list($nic,$deregister_powod) = explode(':',$session->get("1.3.6.1.4.1.3902.1015.1010.1.7.4.1.17.$suma"));
  list($nic,$ven) = explode('"',$session->get("1.3.6.1.4.1.3902.1015.1010.1.1.1.1.1.2.$suma"));
  list($nic,$pasmod) = explode('"',$session->get("1.3.6.1.4.1.3902.1015.1010.5.5.1.29.$suma"));

echo "$signal<br>$onoff<br>$updown<br>$register<br>$ven"

Response on php8.5.1 and php8.5.2:

-22.29148<br><br><br><br>

Response on php8.5.0:

-22.29148<br> 3<br> 1<br>2026/01/28 18:49:19<br>ZTE

In PHP 8.5.0, everything works fine; it reads every SNMP.
After updating to 8.5.2 (and 8.5.1), it only reads the first GET request, and any subsequent ones are not processed. Reverting to 8.5.0 starts working correctly.
Both PHP 8 versions compiled with the same src parameters

Steps to reproduce

list($nic,$signal) = explode('"',$session->get("1.3.6.1.4.1.3902.1015.1010.1.1.1.29.1.5.$sum")); - its OK
list($nic,$oltrx) = explode(':',$session->get("1.3.6.1.4.1.3902.1015.1010.11.2.1.2.".$olt_rx[$rack."/".$card."/".$slot]."."$onu)); **- not read**
list($nic,$onoff) = explode(':',$session->get("1.3.6.1.4.1.3902.1015.1010.1.7.4.1.17.$sum")); **not read**

If I first get and close session, next open and read and close then work. On one session not working good.

Expected behavior
SNMP GET should retrieve every snmp oid, not just the first command executed

Screenshots
No response

Additional context
No response

PHP Version

PHP 8.5.1 (cli) (built: Feb  4 2026 19:35:46) (ZTS)
Copyright (c) The PHP Group
Zend Engine v4.5.1, Copyright (c) Zend Technologies
    with Zend OPcache v8.5.1, Copyright (c), by Zend Technologies

php modules:

router:/var/www/lms/test# php8 -m
[PHP Modules]
bcmath
Core
ctype
curl
date
dom
exif
fileinfo
filter
gd
gmp
hash
iconv
intl
json
ldap
lexbor
libxml
mbstring
mysqli
mysqlnd
openssl
pcntl
pcre
PDO
pdo_mysql
Phar
posix
random
Reflection
session
SimpleXML
snmp
soap
sockets
sodium
SPL
standard
tokenizer
uri
xml
xmlreader
xmlwriter
xsl
Zend OPcache
zip
zlib

[Zend Modules]
Zend OPcache

var_dump($session):

Open session:
object(SNMP)#1 (8) {
  ["info"]=>
  array(3) {
    ["hostname"]=>
    string(12) "10.55.42.100"
    ["timeout"]=>
    int(300000)
    ["retries"]=>
    int(3)
  }
  ["max_oids"]=>
  NULL
  ["valueretrieval"]=>
  int(0)
  ["quick_print"]=>
  bool(false)
  ["enum_print"]=>
  bool(false)
  ["oid_output_format"]=>
  int(0)
  ["oid_increasing_check"]=>
  bool(true)
  ["exceptions_enabled"]=>
  int(0)
}

first get:

object(SNMP)#1 (8) {
  ["info"]=>
  array(3) {
    ["hostname"]=>
    string(12) "10.55.42.100"
    ["timeout"]=>
    int(300000)
    ["retries"]=>
    int(3)
  }
  ["max_oids"]=>
  NULL
  ["valueretrieval"]=>
  int(0)
  ["quick_print"]=>
  bool(false)
  ["enum_print"]=>
  bool(false)
  ["oid_output_format"]=>
  int(0)
  ["oid_increasing_check"]=>
  bool(true)
  ["exceptions_enabled"]=>
  int(0)
}

second get:

object(SNMP)#1 (8) {
  ["info"]=>
  array(3) {
    ["hostname"]=>
    string(12) "10.55.42.100"
    ["timeout"]=>
    int(300000)
    ["retries"]=>
    int(3)
  }
  ["max_oids"]=>
  NULL
  ["valueretrieval"]=>
  int(0)
  ["quick_print"]=>
  bool(false)
  ["enum_print"]=>
  bool(false)
  ["oid_output_format"]=>
  int(0)
  ["oid_increasing_check"]=>
  bool(true)
  ["exceptions_enabled"]=>
  int(0)
}

Operating System

NET-SNMP Version 5.9.4.pre2
OS: Debian kernel compiled 6.1.135
Not work on apache2.4.66 (and cli php8)
Compiled via GCC-13

Compiled configuration php8.5.XX:

'./configure' '--prefix=/opt/php/php8' '--enable-cli' '--enable-fpm' '--enable-enable-opcache' '--enable-sockets' '--enable-soap' '--with-curl' '--with-freetype' '--with-fpm-user=www-data' '--with-fpm-group=www-data' '--with-jpeg' '--with-mysql-sock' '--with-mysqli' '--with-openssl' '--with-pdo-mysql' '--with-xsl' '--with-zlib' '--with-apxs2=/usr/bin/apxs' '--program-suffix=8' '--without-sqlite3' '--without-pdo-sqlite' '--enable-zts' '--with-snmp' '--enable-mbstring' '--with-mbstring' '--enable-gd' '--enable-exif' '--disable-phpdbg' '--with-apxs2=/opt/apache2/usr/bin/apxs' '--with-gmp' '--enable-intl' '--with-ldap' '--enable-pcntl' '--with-password-argon2' '--with-sodium' '--enable-bcmath' '--with-zip'

[devnexen]

I see no major changes after 8.5.0 in this extension, I ll have a look soon-ish. That seems an indirect change (e.,g. from core ?) that SNMP cannot cope with, assuming your two builds are actually really identical.

[devnexen]

Just a few questions:

1/ Would you mind trying a NTS build ?
2/ I assume you are not using opcache (even via ini settings) ?

[safelock1]

I'm recompiled php-8.5.1 without --enable-zts <- I think is NTS build? - this option did not fix the snmp problem

`router:~# php -i | grep -i opcache
Configure Command =>  './configure'  '--prefix=/opt/php/php8' '--enable-cli' '--enable-fpm' '--enable-enable-opcache' '--enable-sockets' '--enable-soap' '--with-curl' '--with-freetype' '--with-fpm-user=www-data' '--with-fpm-group=www-data' '--with-jpeg' '--with-mysql-sock' '--with-mysqli' '--with-openssl' '--with-pdo-mysql' '--with-xsl' '--with-zlib' '--with-apxs2=/usr/bin/apxs' '--program-suffix=8' '--enable-zts' '--without-sqlite3' '--without-pdo-sqlite' '--with-snmp' '--enable-mbstring' '--with-mbstring' '--enable-gd' '--enable-exif' '--disable-phpdbg' '--with-apxs2=/opt/apache2/usr/bin/apxs' '--with-gmp' '--enable-intl' '--with-ldap' '--enable-pcntl' '--with-password-argon2' '--with-sodium' '--enable-bcmath' '--with-zip'
    with Zend OPcache v8.5.1, Copyright (c), by Zend Technologies

Zend OPcache
opcache.blacklist_filename => no value => no value
opcache.dups_fix => Off => Off
opcache.enable => On => On
opcache.enable_cli => Off => Off
opcache.enable_file_override => Off => Off
opcache.error_log => no value => no value
opcache.file_cache => no value => no value
opcache.file_cache_consistency_checks => On => On
opcache.file_cache_only => Off => Off
opcache.file_cache_read_only => Off => Off
opcache.file_update_protection => 2 => 2
opcache.force_restart_timeout => 180 => 180
opcache.huge_code_pages => Off => Off
opcache.interned_strings_buffer => 8 => 8
opcache.jit => disable => disable
opcache.jit_bisect_limit => 0 => 0
opcache.jit_blacklist_root_trace => 16 => 16
opcache.jit_blacklist_side_trace => 8 => 8
opcache.jit_buffer_size => 64M => 64M
opcache.jit_debug => 0 => 0
opcache.jit_hot_func => 127 => 127
opcache.jit_hot_loop => 61 => 61
opcache.jit_hot_return => 8 => 8
opcache.jit_hot_side_exit => 8 => 8
opcache.jit_max_exit_counters => 8192 => 8192
opcache.jit_max_loop_unrolls => 8 => 8
opcache.jit_max_polymorphic_calls => 2 => 2
opcache.jit_max_recursive_calls => 2 => 2
opcache.jit_max_recursive_returns => 2 => 2
opcache.jit_max_root_traces => 1024 => 1024
opcache.jit_max_side_traces => 128 => 128
opcache.jit_max_trace_length => 1024 => 1024
opcache.jit_prof_threshold => 0.005 => 0.005
opcache.lockfile_path => /tmp => /tmp
opcache.log_verbosity_level => 1 => 1
opcache.max_accelerated_files => 10000 => 10000
opcache.max_file_size => 0 => 0
opcache.max_wasted_percentage => 5 => 5
opcache.memory_consumption => 128 => 128
opcache.opt_debug_level => 0 => 0
opcache.optimization_level => 0x7FFEBFFF => 0x7FFEBFFF
opcache.preferred_memory_model => no value => no value
opcache.preload => no value => no value
opcache.preload_user => no value => no value
opcache.protect_memory => Off => Off
opcache.record_warnings => Off => Off
opcache.restrict_api => no value => no value
opcache.revalidate_freq => 2 => 2
opcache.revalidate_path => Off => Off
opcache.save_comments => On => On
opcache.use_cwd => On => On
opcache.validate_permission => Off => Off
opcache.validate_root => Off => Off
opcache.validate_timestamps => On => On
`

[safelock1]

I decided to recompile PHP 8.5.0 (from the clean source src).

After compiling, SNMP stopped working in version 8.5.0.
I compared PHP -i from the working and non-working versions, and it turns out that the problem is in:
-NET-SNMP Version => 5.9.5.2 <- not working ok
+NET-SNMP Version => 5.9.4.pre2 <- WORK OK

I'm retest 8.5.1 with 5.9.4pre2 and write with github information today

On December 31, 2025, due to the CVE-2025-68615 bug, I updated net-snmp in the system.

[safelock1]

I recompiled PHP 8.5.2 from:

1. net-snmp version 5.10.pre2 - not working properly

2. net-snmp version 5.9.5.2 - not working properly

3. net-snmp version 5.9.4.pre2 - everything works fine, but net-snmp contains the CVE-2025-68615 bug

Thank you for your involvement. I'll leave the information about the solution for posterity.